text:
MEA Members Support Rational Gun Safety Reform in the Wake of School Shootings
The firsthand accounts of survivors of school shootings are gut-wrenching, heartbreaking and becoming far too common. As preventable acts of violence continue to take the lives of students and educators across the country, recent polling shows MEA members stand firm in their support of common-sense laws to improve gun safety and prevent school shootings.
A poll conducted in January by Emma White Research shows 94% of MEA members support universal background checks, 93% favor increasing penalties for those who provide a firearm to a minor, 92% back "Red Flag Laws" and 86% support allowing school districts to declare their buildings gun-free zones.
This is not a partisan issue for school employees; the vast majority of MEA's Republican and gun-owning members also support these policies, per analysis of the research.
The same poll revealed that 87% of MEA members support laws requiring gun owners to securely store their firearms. Michigan Senate Democrats proposed such a law, which would also enact criminal penalties for those who fail to secure their weapons and the firearms cause injury or death.
State Sen. Rosemary Bayer, a Keego Harbor Democrat whose district includes Oxford, is a key sponsor of Senate Bills 550-553.
"Safely storing a firearm in the home is a widely supported and commonsense measure that has been shown to save lives and that doesn't seem like much to ask for when you consider it could save the life of a child," Bayer said. "Most shootings of children by children are caused by the guns that were in the house. We can stop this without taking anybody's gun away."
Educators clearly believe the solution to gun violence is not more guns. A broad majority of MEA members oppose providing gun safes in classrooms (82%) or allowing school employees with concealed carry permits to bring their guns to school (73%), including majority opposition from gun-owning MEA members to both ideas.
Want to take action to keep our students and educators safe from guns? Visit www.mea.org/gunsafety to find out how, including filling out our online petition and letting us know what you're willing to do.
Legislation Newsroom Oxford
Students Organize Marches Across U.S.: 'Enough is enough – we demand change'
Aspiring educators connect with young students to explore ways to make a difference
Miriam Garcia
VIEW ALL POSTS BY Miriam Garcia
Education issues central to Whitmer's State of the State address
Issues important to Michigan educators took centerstage Wednesday evening as Gov. Gretchen Whitmer delivered her annual State of the State address at the State Capitol. Among several major announcements, Whitmer called on the Legislature to provide funding — before spring break — for her "MI Kids Back on Track" tutoring proposal, which would provide extra […]
by Miriam Garcia
Faculty at Monroe County Community College vote no-confidence, charge unfair labor practices
Faculty at Monroe County Community College have overwhelmingly approved a no-confidence vote in President Kojo Quartey and filed charges of Unfair Labor Practices against the college, which the faculty association addressed with a show of solidarity at the Board of Trustees meeting on Monday night. A four-page resolution detailed reasons behind the no-confidence vote, including […]


Route 2 Topsham Apartments, located above Route 2 Café, recall the Steam packets that used to sail from Topsham Quay to London once a week, a journey that took three days. Today our beautifully refurbished, fully serviced apartments further recall this era with maritime decorations and with outstanding estuary views looking out across Topsham Quay.
The three centrally located Steam Packet Apartments offer an option that is unique to Topsham: self catering accommodation, self-contained apartments that are fresh, modern, and well-equipped with basic kitchen facilities (induction hob, oven and dishwasher).
The light and airy apartments have self-contained bedrooms, en-suite bath or shower rooms, sitting rooms, free WiFI internet connection, and flat-screen televisions.
1st floor. Double bedroom, en suite shower room, living room with pull-out bed and kitchen area, two large windows overlooking the Topsham quay and estuary. The Estuary apartment is located over the main cafe so there may be some noise on our once-a-month music nights. Otherwise the Café closes at between 6pm and 8pm.
1st floor. Double bedroom, en suite shower room, living room with pull-out bed and kitchen area, one large window overlooking Monmouth Hill.
2nd floor. 2 double bedrooms, en suite bath and shower room, separate WC, living room with pull-out bed and kitchen area, two Velux windows with great views across the estuary to the Haldon Hills and up Monmouth Hill.
Access to the apartments are up a fairly steep flight of stairs. We do not have a lift in the building.
The Apartments are available to let by a three night stay or by the week.
As Topsham has such great food shops, you can shop, live and cook like a local, in comfortable and modern hotel style accommodation.
Route 2 is located on the corner of Holman Way and Monmouth Hill, just off Topsham Quay where there is ample public parking.
The M5 motorway is nearby – exit at junction 30 and follow the signs to Topsham.
Topsham is well served by public transport. Buses run frequently to Topsham from Exeter and Exmouth. The "T" bus stops on Topsham Quay directly opposite of us.Topsham railway station is a 10-minute walk from Route 2 and there are trains to Exeter, Exmouth and further afield around every 30 minutes.
Exeter International Airport is approximately 15 minutes drive away.
Topsham is located on the Route 2 national cycle network. We are a great destination to cycle to and from.
Bicycles can be stored securely in our cycle park.


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On May 29 the Greater Victoria Sports Hall of Fame announced it's 2016 class of inductees who will be honoured at a gala on October 29 at the Westin Bear Mountain. Among the nine inductees is field hockey's Nancy Mollenhauer, a long-time Vancouver Island Ladies Field Hockey Association player and former University of Victoria Vike and Canadian national team player.
A member of the Canadian Women's National Field Hockey dynasty team of the eighties, Nancy Mollenhauer was an integral part Canada's ongoing international success. She competed in two Olympic Games (1984 and 1988), two World Cups (1983 and 1986), and at the 1987 Pan-American Games at which she was named Canada's flag bearer. Nancy won a silver and bronze medal at the 1983 and 1986 World Cups respectively.
Nancy will join Canadian triathlon legend Simon Whitefield, basketball great Gerald Kazanowski, soccer's Simon Keith, as well as Kent Manderville, Mike Spracklen, Randy Bennett (deceased), Bob Moffatt and John and Marilyn Bate for the Class of 2016.
For those interested in attending the event: a table of 10 is $1,000 and individual tickets are $110. with a $50. tax receipt issued. Tickets can be purchased on line at www.gvshof.ca. Click on "Events", then click on "Induction Dinner" to register and pay online.


The surge of digital is our modern day industrial revolution. From the constantly updating streams of content broadcast on social media, to e-commerce chatbots, it has changed every aspect of our lives. From Amazon's drone delivery to the Internet of Things anticipating consumer needs before they even know it, big data and analytics are already having a marked impact on the retail environment.
It is tempting for retailers to see each and every tech development as a shiny new holy grail, providing the long-sought answer to some of the industry's most challenging questions: how do retailers build a better community? How do retailers better measure the path to purchase? – drilling deeper and deeper into data-led shopper insights.
However, at this time of rapid acceleration, retailers are racing to ensure that they are making the most of tech and data at their fingertips. But there is value in pausing and considering how much personalisation is too much. Although big data can provide a solid, scientific ground on which to build a retail marketing strategy, it is not as nuanced as complex shopper behaviour needs it to be, meaning that there are discrepancies between the way it categorises and targets consumers and the shopper realities.
Online personalisation is becoming increasingly effective. We marvel at how often it gets it right, but it's by no means reached its peak – we've all been spuriously recommended a product that completely misses the mark, supposedly based on a previous purchase. Personalisation strategies are firmly on the radar of retail marketers in order to maximise the lifetime value of existing customers and gain new ones. However, the requirement for personalisation extends instore too, with 53% of UK consumers spending less than two hours browsing per physical shopping trip. It seems like an obvious step to use available data to deliver more convenient and personalised shopping experiences to match the ease of online shopping.
Big data analytics will play a major role in shaping the future of the retail industry. But there is a fine line to be walked. The shopper decision-making process is complicated and humans are, by nature, unpredictable. Is hyper-personalisation actually giving consumers what they want? Perhaps not. Data and prediction is the antithesis of serendipity, which provides a huge amount of satisfaction and pleasure for humans. This can be applied to shoppers in that they can discover products that they didn't even know they wanted, or needed, though bricks-and-mortar browsing. Highly-focused targeting online might force a shopper's hand to purchase, but too limited choice can just as easily push them the other way – away from the point of sale. It is beginning to take away the joy of impulse shopping, by increasingly refining which products are pushed to individual consumers – there must be a balance.
Behavioural science has been a common point of reference for some time, helping to identify how shoppers make purchasing decisions. However, this is having to be reconsidered for the digital age.
Whilst there are over 120 heuristics – the hardwired short cuts we use to solve problems and make decisions – identifying and reframing the nine most relevant to purchase decisions provides a base from which to shape strategies and ideas that help drive retail sales. In turn, this framework makes behavioural science useable for retailers and will begin to unpick the reasoning behind shopping, not just the route to get there. Are they thinking fast or slow? Is it a habitual decision? Are they acting on recommendation? Or are they looking for something new? Understanding this is the real key to identifying the optimum level of personalisation and will ensure that retailers don't limit potential sales through overly narrowing recommendations, or overwhelm shoppers with choice when they are not in the right frame of mind to receive it.
The truth is, retail personalisation has to be tailored dependent on the shoppers' frame of mind – this differs according to the time of day, the category, and the platform. An understanding of how behavioural science can drive brand choice amongst shoppers must be the basis for more informed and effective marketing activity. This will help overcome the challenge of giving consumers the right level of personalisation in the era of big data.


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Today, many colleges require students to take at least one online class during the course of their degree work. In fact, if you get a master's degree in education, some of your coursework could be online. Unfortunately, many students have never had any experience with online education. That is why you really want to make sure to give your students as much exposure to it as possible at a young age. Google Classroom is an easy way to help students with this transition because it is super user-friendly, making it a great intro to technology.
Because everything is posted online, Google Classroom gives students access to materials no matter where they are. Gone are the days of lost rubrics or worksheets. Students who are absent can easily access classroom materials from home if necessary–this can really help save both you and your students a lot of stress in the long run.
Because you can set up many different classrooms, Google Classroom is a great tool for differentiation. If you're working on a concept in class and have groups working at two different levels, simply create two different classes for that unit. That way you can better reach out to those who are struggling with their own kind of work without making them feel bad or stupid.
This can help you give out assignments on a more individual basis and really reach out to certain students as well. You can even split everyone into groups that you think they will be able to work the best in. Google Classroom is a great, flexible way to ensure that every student gets just what they need, and you can easily delete and recreate classes as you see fit.
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Overall, using Google Classroom is definitely worthwhile. It can save you a lot of time and energy, and can help you to better prepare your students for the future.


text:
\section{Introduction}

The idea that limitations on the localizability of spacetime events should appear at very small distances is very old and can perhaps be traced back to Wigner and Salecker \cite{t7, t8}. In a thorough investigation on the impact of quantum mechanics on the precision of measurements of distances between points and hence of the metric on curved spacetimes, the first author remarked that ``the establishment of a close network of points in space-time requires a reasonable energy density (...). However, it is not necessary to discuss this in detail because the measurement of the distances between points of the network gives more stringent requirements than the establishment of the network''.

Later, the attention shifted precisely on the conditions imposed on ``the establishment of the network'' itself, that is on the very possibility of giving an operational definition of the concept of spacetime event.
A variety of strategies were devised to attack the problem (see for example
\cite{1,2,3,4,5,6,26q,7,8,8b,t1,t2,t3,t4,t5,t6} and the next Section for a brief discussion), but as far as we know it was Mead \cite{2} who first observed that any attempt to determine the position of an object in a spacetime
region $\cal O$ of size comparable with the error (uncertainty) one is willing to accept entails, by the Heisenberg uncertainty principle, the localization of a non-zero amount of energy in $\cal O$ itself. It is then reasonable, Mead argued, to expect that a too high precision could trigger the formation of an event horizon representing a black hole surrounding $\cal O$, thus preventing any signal to go back to the observer and making the measurement itself meaningless. In this context, we point out that the remark of Einstein himself \cite{AA} that one cannot put an arbitrary amount of energy in a given finite
spatial volume becomes relevant.

The relevant scale for the appearance of such effects was determined as the one of the Planck length

\begin{equation}
L_P=\sqrt{\frac{G\hbar}{c^3}}\simeq 1,6.10^{-33}{\text cm}.
\label{1}
\end{equation}

This point of view has been revived and made more precise in \cite{3} (see \cite{Piacitelli} for a nice review and introduction to more recent developments), where the following program (for flat Minkowski space) was proposed:
\begin{itemize}
\item[1)] Derive operationally meaningful uncertainty relations between coordinates of spacetime events from the requirement of gravitational stability under localization experiments.
\item[2)] Promote the above-mentioned coordinates to the status of quantum operators and commutation relations among them from which the uncertainty relations follow.
\end{itemize}
Making use of a Newtonian approximation of the gravitational potential associated to the localizing energy (see Appendix 2), the following uncertainty relations (DFR relations from now on) were obtained
\begin{eqnarray}
& &c\Delta t\left(\Delta x^1+\Delta x^2+\Delta x^3\right)\geq L^{2}_{P},\label{2}\\
& &\Delta x^1\Delta x^2+\Delta x^1\Delta x^3+\Delta x^2\Delta x^3\geq L^{2}_{P}.\label{3}
\end{eqnarray}
The authors also succeeded in making Step 2) above, thus obtaining a physically motivated model of
a non commutative
(see \cite{10}) quantum spacetime. Moreover, the foundations were laid down for the construction of quantum fields on it. Last but not least, it was
first observed that in all previous works the necessity of a minimal uncertainty length could be traced back to the fact that only spherically symmetric geometries are usually considered. More on this point in the next Section.

Note that equation (\ref{3}) implies that we can determine with arbitrary precision up to two spatial coordinates, say $x^1, x^2$, meaning $\Delta x^1, \Delta x^2 <\epsilon$ with $\epsilon >0$ arbitrarily small. Obviously, we have to pay the price of an arbitrarily large $\Delta x^3$. This is where we see that the extra freedom of non-spherical geometries come into action. However, if we take only $\Delta x^1<\epsilon$, then $\Delta x^2$ \textit{and} $\Delta x^3$ might well remain finite (say of order $L_P$). This would imply, again by the Heisenberg uncertainty relations and in agreement with the results of \cite{9}, that an \textit{infinite} amount of energy could be localized inside an \textit{arbitrarily small} space volume. Since event horizons have been ruled out by assumption, an unphysical naked singularity would arise.

This last observation shows the necessity of going beyond the Newtonian approximation and was the starting point of our investigations. Indeed, in this paper we take exactly the same point of view of \cite{3}, but in our case GR enters the scene through (a refinement of) the so-called \textit{hoop conjecture} (see below), first formulated by Thorne in \cite{12}. We will see in the following that in our proposed spacetime uncertainty relations the above pathologies do not occur and accordingly we will find an upper limit for the space-volume density of energy.

This paper is organized as follows. In section 2 we fix some notations and concepts.
In section 3 we review some "gedanken experimenten" present in the literature.
In section 4 we derive the STUR with a Minkowskian background metric together with some physical consequences.
Section 5 is devoted to an attempt to generalize the STUR to a general curved background.
Section 6 collects some final remarks and conclusions. Finally, in Appendix A we show that the approximations needed to obtain our STUR entail no change in their physical consequences, while in Appendix B we analyze those leading to relations (\ref{2}), (\ref{3}).

We conclude this introduction with two more remarks. First, we make no attempt to tackle Step 2). Second, we do not claim we provide proves, our aim is only to convince the reader by sound and hopefully robust physical arguments that our uncertainty relations are a realistic proposal: being there no chance of a direct experimental verification, they can only be tested by their {\it consequences}.

\section{Notation and preliminaries}

It is well known (see for example \cite{Landau}) that  position, momentum and energy are described in
quantum mechanics
by self-adjoint operators acting on some Hilbert space $\cal H$, while the time $t$ is only a parameter. In what follows, the symbol $\Delta (A)$ indicates the uncertainty of the operator $A$ in some quantum state $\omega$ (for example a vector state $\omega (A)=(\phi,A\phi)$ where $\phi\in \cal H$ and $(\cdot , \cdot)$ indicates the scalar product) as defined by the formula (variance)
\begin{equation}
\Delta (A)= \Delta_{\omega} (A) = \sqrt{\omega((A -\omega (A)I)^2} = \sqrt{\omega(A^2)-\omega(A)^2}
\end{equation}
while ($t$ being a parameter) $\Delta t = t_2-t_1$ where for the sake of definiteness, $t_1$ and $t_2$
should be thought of as the times at which the measurements determining the region $\cal O$ are performed). The symbol $I$ of course indicates the identity operator
on $\cal H$.\footnote{For any spectral value of an operator $A$, there is a state $\omega$ with arbitrary small uncertainty: we see that an absolute lower bound in the uncertainty of one coordinate makes its description by means of an operator impossible. At the same time, in \cite{9} operators describing distances, space and four-volumes defined by \textit{independent} space-time events were defined in terms of coordinates obeying \eqref{2} and \eqref{3}. Lower bounds were found on euclidean distances and four-volumes.}
Once the average is taken, the resulting quantities behave as classical ones. Note that since the functional $\Delta$ is not linear, $\Lambda_{\mu}^{\nu}\Delta (x_{\nu})\neq \Delta (\Lambda_{\mu}^{\nu}x_{\nu})$, where $\Lambda_{\mu}^{\nu}$ is any Lorentz transformation and $x^\mu$ are the coordinates (operators) with $x^0 =t$. Thus, it is not the uncertainty relations that have to be covariant but the quantum operators they come from.

Suppose that now an observer wants to perform a measurement of position and/or time in, say, a flat Minkowsky spacetime and he is willing to accept an error $\Delta x^i$ ($i=1, 2, 3$), $\Delta t$. Then, he will have to concentrate a certain amount of matter-energy in a spacetime region $\cal O$ of corresponding size. Should this region be sufficiently small, it is reasonable to expect that quantum effects should no more be negligible. One is thus led to consider the usual Heisenberg uncertainty relations
\begin{equation}\label{7}
\Delta x^i \Delta p^j \geq \delta_{ij}\frac{\hbar}{2} \qquad\qquad\qquad i,j=1,2,3
\end{equation}
which, in our relativistic setting, should be complemented with the time-energy relations
\begin{equation}\label{6}
\Delta t \Delta E \geq \frac{\hbar}{2},
\end{equation}
and draw the conclusion that the measurement entails an energy transfer to the (dynamic) spacetime. In particular, we see that very high energies will correspond to smaller errors in time. If in addition one requires small space uncertainties, a black hole could be produced thus preventing any signal to come out from the localization region and making the measurement itself meaningless.

As remarked in the introduction, this line of reasoning seems to have a long history and was first put on quantitative grounds by Mead in 1964 \cite{2}. There, under the assumption of spherical symmetry (i.e. $\Delta R\simeq\Delta x^1 \simeq\Delta x^2\simeq\Delta x^3$), the author derived the relation
\begin{equation}\label{minlenght}
\Delta R \geq L_P
\end{equation}
and concluded from it that an absolute minimal length had to exist.

It is interesting to note that the same result was obtained in a string theoretical context (see for example \cite{Ciafaloni}) and by model-independent considerations in \cite{Maggiore}. In both cases, the starting point were the Generalized Uncertainty Relations (GUP)
\begin{equation}
\Delta R \geq\frac{\hbar}{\Delta p} + \alpha^{\prime}\Delta p
\label{me}
\end{equation}
($\alpha^{\prime}$ is a constant depending on Regge's slope and the gravitational constant $G$), from which once more under the assumption of spherical symmetry \eqref{minlenght} follows by minimization of the second member.

 Finally, we stress that the position-momentum uncertainty relations are of a completely different nature than the time-energy one. More precisely, the first ones are relations between specific averages (variances) of quantum operators while the second ones are obtained by evaluating the transition probability between states with energies differing by an amount $\Delta E$. The difficulty stems from the impossibility to associate a bona fide self-adjoint operator with time in the case of a non-trivial (i.e. lower bounded) energy spectrum, but it has been circumvented in \cite{Brunetti} by making use of the concept of operator-valued measures (see \cite{Ludwig} for a thorough discussion). The time-energy uncertainty relation (\ref{6}) was then recovered by a slight modification of the usual position-momentum argument. However, the following arguments
should be considered independent of such details.

\section{Minimal uncertainty length in the literature: a review}

In this section we give a brief and certainly incomplete account of how the concept of minimal uncertainty is addressed in the
literature. We already pointed out the observation first made in \cite{3}: very often the conclusion that a minimal uncertainty exists can be traced back to the (implicit or explicit) assumption that the geometry of the problem be spherical.

We start with the papers \cite{t5,t6}. Since they were built on the ideas of \cite{t7,t8}, the main concern of the authors is limitations on the measurement of distances between different spacetimes points. However, they give a quantitative estimate of the minimal uncertainty in the localization of each single point which is obtained by invoking the Schwarzschild metric.

A wealth of localization ``gedanken experimenten'' is presented in \cite{5}, where fluctuations of the spacetime metric are analyzed making use of photons instead of target massive particles (together with some considerations on the Einstein equations). We will do the same in the following. In the first experiment a microscope-type construction is presented, namely a photon scattered by a target particle. Here, the Newtonian gravitational interaction between
the photon and the target particle is calculated together with the suggested modification of the Heisenberg
relation leading to relation (\ref{me}) without invoking black hole physics. In any case, the Newtonian
gravitational field is given in the form $\sim\frac{1}{r^2}$ and so spherical symmetry is
implicitly assumed. The same assumption affects the description of the time resolution of synchronizing clocks in terms of the
gravitational field generated by photons: a time-time component of a spherically symmetric metric is introduced.
In the second example, a minimal uncertainty length is analyzed within a path integral formulation of
quantum gravity. At a certain point the author denotes with $\ell$ "the radius of the region" and
so, once again, spherical symmetry comes on stage. In \cite{t1} another interesting localizing experiment based on clocks and on the Heisenberg uncertainty principle is presented and an uncertainty relation involving the volume $\Delta V$ of the region to be localized and the time coordinate is found. The author denotes $\Delta V={(\Delta x)}^3$ and imposes that the "Schwarzschild radius
should not exceed the uncertainty $\Delta x$": thus, the condition
$\Delta x=\Delta y=\Delta z$ is implicitly assumed. Even the minimal uncertainty found in \cite{t2} using the GUP (\ref{me}) is obtained using a spherical black hole argument. More references presenting arguments plagued by the assumption of spherical geometry can be found in \cite{Piacitelli}.

The necessity of considering more general geometries is however clearly stressed in \cite{8b}, where an interesting localizing
experiment using an interferometer is proposed. The authors provide sound arguments to show that the uncertainty in one single coordinate can be reduced to arbitrarily small values, but are only able to provide quantitative results in a spherical case where a minimal uncertainty is once again found.

We conclude this section by mentioning that not only uncertainties in coordinates and distances have been considered in the literature. For example, much in the spirit of the investigations of Wigner himself, in \cite{t4}, \cite{t3} the main interest are the quantum fluctuations of the metric. Spherical symmetry is assumed in \cite{t3}, while in \cite{t4} only asymptotic flatness of static spacetime is needed. In both papers a Heisenberg-type uncertainty relation is found between the metric and a ``conjugate'' quantity, so that there is no minimal uncertainty.

\section{Minkowskian background}

\subsection{Spherical case}
As it should now be clear, localization in some spacetime region $\cal O$ will mean producing a (quantum) state confined there. We start by considering an experiment performed by an observer in a flat Minkowskian spacetime. It should be no surprise that in what we call spherical case (that is $\Delta x^1 \simeq \Delta x^2 \simeq \Delta x^3 \simeq \Delta R /\sqrt{3}$, $\Delta R$ being the radius of the localization sphere) a completely satisfactory answer can be given. We start by presenting a separate treatment of this situation.

The metric outside the space volume $V^{(3)}$ where an energy $\Delta E$ is concentrated is
\begin{equation}
ds^{2}_{exp}=\frac{dr^2}{\left(1-\frac{2G\Delta E}{c^4 r}\right)}+r^2d{\Omega}^2-
\left({1-\frac{2G\Delta E}{c^4 r}}\right)dt^2.\label{4}
\end{equation}
Of course, we set $\Delta E=c^2 \Delta M$, $\Delta M$ being then the ADM mass-energy of the experiment.
Since the configuration is spherical, gravitational radiation is absent so that the exterior metric is static. Note that, due to spherical symmetry, this will be true irrespective of the duration $\Delta t$ of the experiment, where of course $t$ is the time measured by an observer at spatial infinity.
Making use of the Komar integral, it is clear that for any $r>\Delta R$ the mass-energy of the experiment is simply $\Delta M$. From (\ref{4}), the condition that no black hole is formed reads
\begin{equation}
\frac{G\Delta E}{c^4}<\frac{\Delta R}{2}.
\label{5}
\end{equation}
As remarked above, our observer measures the time $t$ and the energy in terms of it. He can therefore use the Heisenberg relation (\ref{6}) to estimate the {\it average} energy $\Delta E$ (recall the discussion in section 2)
of the configuration, so that condition (\ref{5}) becomes
\begin{equation}
c\Delta R\Delta t\geq L^{2}_P.
\label{8}
\end{equation}
This is the time-space uncertainty relation.

Since $\Delta E \geq c\Delta p$, from (\ref{7}) and condition (\ref{5}) we obtain
\begin{equation}
\Delta R\Delta x^1\Delta x^2\Delta x^3\geq L^{2}_{p}
\sqrt{{(\Delta x^1)}^2{(\Delta x^2)}^2+{(\Delta x^2)}^2{(\Delta x^3)}^2+
{(\Delta x^1)}^2{(\Delta x^3)}^2}\label{9}.
\end{equation}
In the spherical case, this reads $\Delta x^i\geq L_P, i=1,2,3$, i.e. a minimal
uncertainty length appears
in agreement with (\ref{minlenght}) and (\ref{me}).
Furthermore, in this particular situation, our results agree with the ones in (\ref{3}).

\subsection{General case}

The main problem when considering more general geometries than the spherical one is the absence of general theorems guaranteeing that no black holes are formed, independently of the dynamics governing the energy-matter motion.
In fact solving the global Cauchy problem remains a formidable task at the present day, apart from
the remarkable work of Christodoulou \cite{C1,C2} about spherical collapse in
the presence of classical scalar fields.\\
For this reason, we resort to the so called hoop conjecture (see \cite{12,13,14,15,16,17,18,19}). In its original version, it states that

\begin{itemize}
\item horizons form when and only when a mass $M$ is concentrated into a region whose circumference
in every direction satisfies $C\leq 4\pi M\frac{G}{c^2}$.
\end{itemize}
For example, this would imply that a mass confined in a cylinder with a small base radius but a sufficiently large height would
not produce an horizon. The statement is purposely imprecise. As the mass $M$ we could take the ADM mass or
a quasi-local one such as the Tolmann mass \cite{20}. The study of event horizon formation is very
complicated since it is a global concept available only to "omniscient" observers (see \cite{14}). For these reasons,
in the literature, geometrical and more tractable
objects as apparent horizons and trapped surfaces (see \cite{w1,w2,w3}) are often used.
In fact, the formation of trapped surfaces and apparent horizons represents an
indication of the formation of black holes, via the cosmic censorship conjecture \cite{w4}.\\
In any case the hoop conjecture can also be stated in terms of the surface of the horizon $A_H$ and the mass $M$, according to the so called Penrose's isoperimetric-type conjecture (see \cite{15,21}). For a stationary black hole we have \cite{13}
\begin{equation}
A_E<A_H \leq 16\pi \frac{G^2}{c^4}M^2,
\label{10}
\end{equation}
$A_E$ being the apparent horizon. As a result, the existence of an apparent horizon implies the existence of
an event horizon enclosing it. More generally, denoting
with $A_i$  the minimal area of a surface enclosing an apparent horizon,
Penrose's isoperimetric conjecture states that
\begin{equation}
A_i\leq 16\pi \frac{G^2}{c^4}M^2.
\label{100bb}
\end{equation}
To ensure that no black hole is formed,
we need to invert inequality (\ref{100bb}).
Furthermore, we study situations in which the mass-energy $M$ is localized within a region of area $A$
with $A\geq A_i$.
As a result,
we can with no loss of generality consider the inequality
\begin{equation}
A \geq 16\pi \frac{G^2}{c^4}M^2,
\label{11}
\end{equation}
so that {\it in no case} the formation of an event horizon enclosing the localizing
area $A$ is possible.
This is our starting point.
By considering a surface $\Delta A$ enclosing a mass $\Delta M$ and again putting $\Delta E=c^2 \Delta M$, we have
\begin{equation}
\Delta A \geq 16\pi\frac{G^2}{c^8}{(\Delta E)}^2.
\label{12}
\end{equation}
Suppose now the localization region is a box with edges $\Delta x^1,\Delta x^2,
\Delta x^3$. Then
\begin{equation}
\Delta A \sim \frac{\Delta x^1\Delta x^2+\Delta x^1\Delta x^3+\Delta x^2\Delta x^3}{{\alpha}^2},
\label{13}
\end{equation}
where the normalization constant $\alpha$ will be determined later.\\
Concerning the energy $\Delta E$, from equation (\ref{6}) we again have
\begin{equation}
\Delta E\geq\frac{\hbar}{2\Delta t}.
\label{14}
\end{equation}
Furthermore, since the localization experiment is performed by concentration of mass-energy, we have
\begin{equation}
{(\Delta E)}^2\geq c^2
\left[{(\Delta p_{x^1})}^2+{(\Delta p_{x^2})}^2+{(\Delta p_{x^3})}^2\right],
\label{15}
\end{equation}
and from (\ref{7}) we deduce that
\begin{equation}
{(\Delta E)}^2\geq\frac{c^2{\hbar}^2}{4}\left[{\left(\frac{1}{\Delta x^1}\right)}^2+
{\left(\frac{1}{\Delta x^2}\right)}^2+{\left(\frac{1}{\Delta x^3}\right)}^2\right].
\label{16}
\end{equation}
Note that inequality (\ref{16}) holds for any type of localizing mass-energy.
From (\ref{13}), (\ref{14}) and (\ref{12}) we obtain
\begin{equation}
{(c\Delta t)}^2\left(\Delta x^1\Delta x^2+\Delta x^1\Delta x^3+\Delta x^2\Delta x^3\right) \geq
4\pi{\alpha}^2L^{4}_{P}.
\label{17}
\end{equation}
Comparison with the spherical case gives $4\pi {\alpha}^2=1$. We can use inequality (\ref{16}) to obtain the space-space uncertainty relation. To this purpose first notice that the following inequality holds
\begin{equation}
{\left(\frac{1}{\Delta x^1}+\frac{1}{\Delta x^2}+\frac{1}{\Delta x^3}\right)}^2\geq
{\left(\frac{1}{\Delta x^1}\right)}^2+
{\left(\frac{1}{\Delta x^2}\right)}^2+{\left(\frac{1}{\Delta x^3}\right)}^2. \label{18}
\end{equation}
Estimating the energy $\Delta E$ by the left hand side of (\ref{18}) we obtain a less precise result, i.e. we ask that the area $\Delta A$ be greater
than a quantity which in turn is greater than the energy. Nevertheless,
we argue in Appendix A that this causes no change in the physical content of the uncertainty relation. Summing up, our final expression for the STUR is
\begin{eqnarray}
{(c\Delta t)}^2\left(\Delta x^1\Delta x^2+\Delta x^1\Delta x^3+\Delta x^2\Delta x^3\right) \geq
L^{4}_{P},\qquad\quad\label{19}\\
{(\Delta x^1)}^2 {(\Delta x^2 )}^2 {(\Delta x^3 )}^2 \geq L^{4}_{P}
\left(\Delta x^1\Delta x^2+\Delta x^1\Delta x^3+\Delta x^2\Delta x^3\right).\label{20}
\end{eqnarray}
Furthermore, it easy to see that making use of the following crude estimates for
(\ref{19}) and (\ref{20}) respectively
\begin{eqnarray}
(a+b+c)^2\geq ab+bc+ac, \label{21}\\
(ab+bc+ac)^3\geq a^2 b^2 c^2,\quad\label{22}
\end{eqnarray}
with $a=\Delta x^1, b=\Delta x^2, c=\Delta x^3$,
we get the DFR relations (\ref{2}) and (\ref{3}).

\subsection{Some physical consequences}

To start with, rewrite (\ref{20}) in the form
\begin{equation}
\Delta x^1\Delta x^2\Delta x^3 \geq L^{4}_{P}\left(\frac{1}{\Delta x^1}+\frac{1}{\Delta x^3}+\frac{1}{\Delta x^3}\right).
\end{equation}
If $\Delta x^1<\epsilon$ ($\epsilon>0$), the other uncertainties being arbitrary, we obtain
\begin{equation}
\Delta x^1\Delta x^2\Delta x^3\geq \frac{L^{4}_{P}}{\epsilon}.
\label{23}
\end{equation}
We see then that if an uncertainty on a single spatial coordinate is arbitrarily small, the spatial volume must increase accordingly. Not only no minimal uncertainty length arises, but localization of an infinite energy in a finite volume is forbidden.\\
The same conclusion can be drown in the case $\Delta x^1<\epsilon_1, \Delta x^2<\epsilon_2$ ($\epsilon_1,\epsilon_2 >0$), but now we also see that there is no minimal surface in the sense that the product of two linear uncertainties can be made arbitrarily small. In fact, we have
\begin{equation}
\Delta x^1\Delta x^2\Delta x^3\geq L^{4}_{P}\left(\frac{1}{\epsilon_1}+\frac{1}{\epsilon_2}\right).
\label{24}
\end{equation}
Moreover, by taking the third power of (\ref{20}) and estimating the resulting right-hand side by (\ref{22}) we easily
obtain
\begin{equation}
\Delta x^1\Delta x^2\Delta x^3\geq L^{3}_{P},\label{26}
\end{equation}
i.e. a lower bound for the space volume appears. Finally, (\ref{19}) and (\ref{20}) together imply
\begin{equation}
c\Delta t\Delta x^1\Delta x^2\Delta x^3\geq L^{4}_{P}.
\label{25}
\end{equation}
meaning that an analogous result holds for the four-volume. On the other hand, if we put $\rho\Delta x^1\Delta x^2\Delta x^3=\Delta M$ ($\rho$ being thus the density) in (\ref{11}) and take advantage of (\ref{12}) and (\ref{20}) we obtain
\begin{equation}
\rho<\frac{1}{4\sqrt{\pi}}\frac{c^2}{GL_P^2}\sim {\rho}_{P},
\label{27}
\end{equation}
where ${\rho}_{P}$ indicates Planck's density. Thus, independently of the geometry of the localization zone, an upper limit for the density appears. In view of (\ref{26}) this should be no surprise, but we stress that GR alone cannot account for this result: to rule out singular distributions of matter-energy one needs quantum mechanics.
Concerning relation (\ref{19}), when the "spatial" part
$\left(\Delta x^1\Delta x^2+\Delta x^1\Delta x^3+\Delta x^2\Delta x^3\right)$
goes to infinity, $\Delta t$ can be made arbitrarily small.
Conversely, when $\Delta x^1\sim\Delta x^2\sim\Delta x^3\sim L_p$, we have $c\Delta t\geq L_p$, showing that,
limited to the spherical case, we have a minimum uncertainty also in the time coordinate.\\
Our next considerations concern the possible underlying quantum structure. The determination of commutators among quantum operators that could give rise to our STUR is certainly not a simple task. Nevertheless, some partial conclusions can be drawn thanks to the fact that in our approach the DFR relations appear as an approximation to the STUR themselves and moreover provide exactly the same result in the spherical case. We look at this fact as a hint that the commutation relations obtained in \cite{3} could be viewed as a limiting case of the ones giving rise to the STUR.\\
In view of the generalization to curved backgrounds, we conclude this section by the following remarks. Introducing the surfaces
\begin{equation}
\Delta A^{0}={(c\Delta t)}^2,\; \Delta A^{1}=\Delta x^2\Delta x^3,\;\Delta A^{2}=\Delta x^1\Delta x^3,\; \Delta A^{3}=\Delta x^1\Delta x^2.
\label{28}
\end{equation}
the STUR (\ref{19}) and (\ref{20}) become
\begin{eqnarray}
\Delta A^{0}\left(\Delta A^{3}+\Delta A^{1}+\Delta A^{2}\right)\geq L^{4}_{P},\qquad\quad\label{29}\\
\Delta A^{3}\Delta A^{1}\Delta A^{2}\geq L^{4}_{P}\left(\Delta A^{3}+\Delta A^{1}+\Delta A^{2}\right).\label{30}
\end{eqnarray}
Moreover, by making use once more of (\ref{22}), we obtain
\begin{equation}
\Delta A^{3}\Delta A^{2} +\Delta A^{3}\Delta A^{1}+\Delta A^2 \Delta A^{1}\geq L^{4}_{P},
\label{30b}
\end{equation}
Note that, together with (\ref{29}), this is exactly the same structure of the DFR relations, albeit in terms of the surfaces $\Delta A^{0}, \Delta A^{1}, \Delta A^{2}, \Delta A^{3}$. We believe that this might be more than a simple formal manipulation, since we have seen that GR (more precisely condition (\ref{12})) and quantum mechanics seem to lead naturally to terms proportional to $L^{4}_{P}$. More importantly, the commutators
$[A^{\alpha},A^{\beta}]$ (where $\alpha, \beta=0,\dots,3$)
between the quantum
operators $A^{\alpha}$ are known, being formally identical
to the commutators between the spacetime coordinates present in \cite{3}. The next step would be to find explicit expressions for the coordinate operators $t,x,y,z$ in terms of the $A^{\alpha}$'s and calculating the corresponding commutators.

\section{Curved background: an attempt}

The extension of our results to the case of a general curved background presents one main difficulty. Of course, we still have condition (\ref{12}) at our disposal, but unfortunately we cannot use Heisenberg relations (\ref{6})
and (\ref{7}) any more. The main problem is that, thanks to the equivalence principle, there
is not a simple manner to isolate the energy contribution inside
the localizing "box" (the experiment) from the
rest of the mass-energy distribution, i.e for a non-isolated system. However, in the literature
(see \cite{26,27,28,29} and for a comprehensive review \cite{30} and references therein) the
concept of quasi-local mass has been introduced
to measure the energy of a system within a closed compact
orientable space-like two-surface by means
of a energy-momentum four-vector depending on the first fundamental form on the two-surface itself,
the second fundamental form and null normals which define a preferred basis for the fibers of the
normal bundle. It is a common opinion that the most promising was proposed in \cite{29} by means of
the Hamiltonian formulation of GR.
Obviously, the most important  requirements for a quasi-local mass are as follows.
\begin{enumerate}
\item The ADM and Bondi mass should be recovered respectively at spatial and null infinity.
\item When the surface degenerates to a point, correct limits must be obtained.
\item The quasi-local mass must be non-negative and zero for any space-like two surface in a
flat Minkowskian background.
\end{enumerate}
The conditions above are not trivial to fulfill. We do not enter in more details and
thereafter denote with the symbol $E_{ql}$ the quasi-local energy.\\
Furthermore, for our purposes, it seems to be reasonable to use the formalism introduced in
\cite{23} and \cite{24}.
Then, $g_{\mu\nu}$ being the background metric, we define
\begin{eqnarray}
h_{\mu\nu}=g_{\mu\nu}+{\gamma}_{\mu\nu},\;
{\gamma}^{0}=\frac{1}{\sqrt{|g_{00}|}},\;{\gamma}^{i}=0,\;
{\gamma}_i=\frac{g_{0i}}{\sqrt{|g_{00}|}},\label{42}\\
ds^2=d{\sigma}^2-c^2dT^2,\qquad\qquad\qquad\label{43}
\end{eqnarray}
where
\begin{equation}
d{\sigma}^2=h_{ik}dx^i dx^k,
\label{44}
\end{equation}
with $T$ given by
\begin{equation}
T=\int\sqrt{|g_{00}|}dt+\int\frac{g_{0i}}{c\sqrt{|g_{00}|}}dx^i,\;\;\;i=1,2,3.
\label{39}
\end{equation}
In this way the line element is written only in terms of observable
quantities, i.e. $T$ and $\sigma$. As a consequence, we propose to substitute inequality
(\ref{6}) for a flat background with
\begin{equation}
{\Delta}E_{ql}\Delta T\geq\frac{\hbar}{2}.
\label{z1}
\end{equation}
Expression (\ref{z1}) is generally well defined and reduces to inequality (\ref{6}) in a flat
background.
As a consequence, using (\ref{z1}) and (\ref{12}) we can write the time-space uncertainty relation as
\begin{equation}
\Delta A^{00}\Delta A \geq L^{4}_{P},\;\;\;\Delta A^{00}={(c\Delta T)}^2,
\label{40}
\end{equation}
where $\Delta A$ is now a surface depending on the
non-flat background metric (\ref{43}) and cannot be expressed in the simple form (\ref{13}).\\
The space-space relation is much more involved and we have not been able to find a reasonable generalization
for a curved background. However, some interesting inequalities can
be suggested.\\
First of all,
if we consider a stationary background, $h_{ik}$ does not depend
on the time $T$ and as a result, we can write equations (\ref{19}) and
(\ref{20}) in a form more appropriate for a curved background without any explicit
reference to the spatial coordinates. We obtain
\begin{eqnarray}
& &c\Delta T\Delta V^{(3)} \geq L^{4}_{P},\label{45}\\
& &{(\Delta V^{(3)})}^2\geq L^{4}_p\;\Delta A. \label{450}
\end{eqnarray}
Obviously, expressions (\ref{45}) and (\ref{450})
reduce to (\ref{19}) and (\ref{20}) in a Minkowskian background by writing the
spatial volume and the total surface of the localizing "box" in terms of Cartesian coordinates.
We regard expressions (\ref{40}), (\ref{45})
and (\ref{450}) as an indication that proper times, surfaces and volumes may be the natural object to be quantized.\\
Taking into account that inequality (\ref{26}) must still hold in a
\textit{stationary} general background ($\Delta V^{(3)}\geq L^{3}_P$),
 equation (\ref{45}) together with (\ref{40}) entails an upper limit to the proper density $\rho$. In fact, in analogy with the flat case, we can write the proper mass (see \cite{18}) $\Delta M_p$ (the mass inside the proper three volume
$\Delta V^{(3)}$) as $\rho\Delta V^{(3)}=\Delta M_p$. As a consequence, recalling (\ref{12}) we see that inequality (\ref{27}) is still valid independently of the geometry of the configuration. Once more,
we stress that this result is a consequence of \textit{both} GR
and quantum mechanics.\\
In any case, for a general non-stationary background, it seems reasonable to
take advantage of the results in (\ref{25}) to obtain
\begin{equation}
\Delta V^{(4)} \geq L^{4}_{P},
\label{41}
\end{equation}
$\Delta V^{(4)}$ being the invariant four-volume.
Our method allows no further generalizations, since in a non-stationary background the four-volume (\ref{41})
cannot be put in the form (\ref{45}), because of the time dependence of the metric $h_{ik}$ .\\
Conversely, if we adopt inequality (\ref{45}) also for a non-stationary background, expression
(\ref{41}) cannot be directly inferred.\\
Summarizing, for a stationary background spacetime we use (\ref{40}), (\ref{45})
and (\ref{450}). Obviously they are not independent. In fact, starting with (\ref{450}) and using
(\ref{40}), we obtain inequality (\ref{45}). For a general time-dependent spacetime, we use
(\ref{40}) and (\ref{41}).\\
Let us conclude this section with a remark.
Recently, in \cite{222} it has been advocated that energy can be localized in GR by means of a
generalization of the Tolman mass (\cite{20}) to a generic non-static background. The expressions  for the energy and momentum proposed there are
\begin{eqnarray}
& &\tilde{E}=\frac{c^4}{4\pi G}\int R^{\mu}_{\nu}u^{\nu}u_{\mu}\sqrt{-g}d^4 x,\;\;\;
\mu,\nu=(0,1,2,3),\label{35}\\
& &{\tilde{p}}^{\alpha}=\frac{c^4}{4\pi G}\int R^{\alpha}_{\nu}u^{\nu}\sqrt{-g}d^4 x,\;\;\;
\alpha=(1,2,3),\label{36}
\end{eqnarray}
where $u^{\nu}$ stands for the four-velocity of the observer. The main idea is that the energy is encoded by the
Ricci tensor $R_{\mu\nu}$. We stress that if (\ref{35}) and (\ref{36}) are correct, gravitational waves
do not carry energy.\\
For a free-falling observer we have $u^{\nu}=u_{\nu}=(1,0,0,0)$. Since (\ref{35})
is an invariant four-scalar, it is clear that he/she computes the
Tolman mass (multiplied by its proper time), i.e. the mass ``without gravity''. As a consequence, in \cite{222} the following uncertainty relations are proposed
\begin{eqnarray}
\Delta E\Delta t\geq\frac{\hbar}{2}\;\;\rightarrow\;\;\Delta\tilde{E}\geq\frac{\hbar}{2},\;\;\label{37}\\
\Delta p^{\alpha}\Delta x^{\alpha}\geq \frac{\hbar}{2}\;\;\rightarrow\;\;
\Delta{\tilde{p}}^{\alpha}\geq\frac{\hbar}{2}.\label{38}
\end{eqnarray}
Thanks to the observations above concerning a free-falling observer, to impose condition (\ref{12}) to (\ref{37}) we can divide the quantity $\Delta\tilde{E}$ by the chrono-invariant time given by (\ref{39}).
As a consequence, using (\ref{37}) the time-space uncertainty relation becomes the one given by
(\ref{40}). For the space-space relation,
we could use expression
(\ref{38}), but this cannot be written in the form (\ref{16}) since the norm of a vector is given in terms
of the background metric. Hence, we are forced to use again the arguments leading to (\ref{45})
and (\ref{41}).

\section{Conclusions}

In this paper we obtained the STUR from Quantum Mechanics and classical GR. More precisely, we made use of the Heisenberg uncertainty relations and of the observation that the formation of black holes due to concentration of energy makes the measurement of position operationally meaningless. As advocated in \cite{3}, the STUR then follow from a sound physical input.

To start with, we obtained STUR in a flat background. Then, we have generalized them to general curved backgrounds
with particular attention to the stationary case.
Our STUR appear completely physically reasonable, in the sense that an infinite energy can never be localized in a finite volume.
Furthermore, in agreement with \cite{3}, we found no minimal uncertainty while a natural lower bound for the Lorentz invariant (or general invariant in the case of GR) four-volume appears together with an upper limit for the space-volume density. We stress that our results coincide, in the case of a spherical geometry, with the ones obtained
by making use of the GUP, that is, by allowing the Heisenberg relations to be modified by gravity.\\
Some indications were given for the possible underlying quantum structure,
but we were not able to find the commutators implying our STUR. This will be the subject of a future work.

\section*{Appendix A}
The exact form of our STUR (i.e. without making use of the approximation (\ref{18})) is
\begin{eqnarray}
{(c\Delta t)}^2\left(\Delta x^1\Delta x^2+\Delta x^1\Delta x^3+\Delta x^2\Delta x^3\right)\geq
L^{4}_{P},\label{B1}\qquad\\
{(\Delta x^1)}^2{(\Delta x^2)}^2{(\Delta x^3)}^2
\left(\Delta x^1\Delta x^2+\Delta x^1\Delta x^3+\Delta x^2\Delta x^3\right)\geq \nonumber\\
\geq L^{4}_{P}\left({(\Delta x^1)}^2{(\Delta x^2)}^2+{(\Delta x^2)}^2{(\Delta x^3)}^2+
{(\Delta x^1)}^2{(\Delta x^3)}^2\right).\label{B2}
\end{eqnarray}
First of all observe that we can write (\ref{B2}) as
\begin{eqnarray}
\Delta x^1\Delta x^2\Delta x^3 \geq L^{4}_{P}(\Delta x^1\Delta x^2 +\Delta x^2\Delta x^3 +\Delta x^3\Delta x^1)^{-1}\times \nonumber\\
\times\left(\frac{\Delta x^1\Delta x^2}{\Delta x^3}+\frac{\Delta x^2\Delta x^3}{\Delta x^1}+\frac{\Delta x^3\Delta x^1}{\Delta x^2}\right). \qquad\qquad
\label{B3}
\end{eqnarray}
Consider now the case $\Delta x^1<\epsilon$ ($\epsilon>0$), $\Delta x^2,\Delta x^3>\Delta x^1$. Then
\begin{equation}
\Delta x^1\Delta x^2\Delta x^3 \geq \frac{L^{4}_{P}}{3\Delta x^2\Delta x^3}\times\frac{\Delta x^2\Delta x^3}{\Delta x^1}=\frac{L^{4}_{P}}{3\Delta x^1},
\end{equation}
in agreement with (\ref{23}). For $\Delta x^1<\epsilon_1, \Delta x^2<\epsilon_2$ ($\epsilon_1>0, \epsilon_1>0$) and $\Delta x^3>\Delta x^2, \Delta x^2$ we have, this time in agreement with (\ref{24}),
\begin{eqnarray}
\quad \Delta x^1\Delta x^2\Delta x^3\geq \frac{L^{4}_{P}}{2(\Delta x^2\Delta x^3+\Delta x^3\Delta x^1)}\times\left(\frac{\Delta x^2\Delta x^3}{\Delta x^1}+\frac{\Delta x^3\Delta x^1}{\Delta x^2}\right)= \nonumber \\
=\frac{L^{4}_{P}}{2}\left(\frac{\Delta x^2}{\Delta x^1(\Delta x^1+\Delta x^2)}+\frac{\Delta x^1}{\Delta x^2(\Delta x^1+\Delta x^2)}\right)\geq \qquad\qquad\nonumber \\
\geq\frac{L^{4}_{P}}{2}\left(\frac{\Delta x^2}{(\Delta x^1+\Delta x^2)^2}+\frac{\Delta x^1}{(\Delta x^1+\Delta x^2)^2}\right)= \qquad\qquad\quad\nonumber \\
=\frac{L^{4}_{P}}{2}\left(\frac{1}{(\Delta x^1+\Delta x^2)}\right)\geq   \frac{L^{4}_{P}}{2(\epsilon_1+\epsilon_2)}.\qquad\qquad\qquad\qquad
\end{eqnarray}
The case $\Delta x^i<\epsilon_i$ and $\epsilon_i$ arbitrarily small ($i=1,2,3$) is forbidden by (\ref{B2}). To estimate the three-volume first note that we can suppose with no loss of generality that $\Delta x^1\Delta x^2=\max \{\Delta x^1\Delta x^2, \Delta x^2\Delta x^3, \Delta x^1\Delta x^3 \}$. Then from (\ref{B2}) we obtain
\begin{eqnarray}
{(\Delta x^1)}^2{(\Delta x^2)}^2{(\Delta x^3)}^2\geq \frac{L^{4}_{P}}{3}\Delta x^1 \Delta x^2 \geq \nonumber \\
\geq \frac{L^{4}_{P}}{9}\left(\Delta x^1\Delta x^2+\Delta x^1\Delta x^3+\Delta x^2\Delta x^3\right).
\end{eqnarray}
By taking the third power of both sides and using (\ref{22}), we arrive at
\begin{equation}
\left[{(\Delta x^1)}^2{(\Delta x^2)}^2{(\Delta x^3)}^2\right]^3\geq \frac{L^{12}_{P}}{9^3}{(\Delta x^1)}^2{(\Delta x^2)}^2{(\Delta x^3)}^2,
\end{equation}
which gives
\begin{equation}
\Delta x^1 \Delta x^2 \Delta x^3\geq \frac{L^{3}_{P}}{3\sqrt{3}}.
\end{equation}
Finally, for the four-volume we obtain
\begin{eqnarray}
{(c\Delta t)}^2{(\Delta x^1)}^2{(\Delta x^2)}^2{(\Delta x^3)}^2\geq \qquad\qquad\quad \label{B4}\\
L^{8}_{P}
\frac{\left({(\Delta x^1)}^2{(\Delta x^2)}^2+{(\Delta x^2)}^2{(\Delta x^3)}^2+
{(\Delta x^1)}^2{(\Delta x^3)}^2\right)}
{{\left(\Delta x^1\Delta x^2+\Delta x^1\Delta x^3+\Delta x^2\Delta x^3\right)}^2}.\nonumber
\end{eqnarray}
and by the same assumption then for the three-volume
\begin{eqnarray}
\frac{\left({(\Delta x^1)}^2{(\Delta x^2)}^2+{(\Delta x^2)}^2{(\Delta x^3)}^2+
{(\Delta x^1)}^2{(\Delta x^3)}^2\right)}
{{\left(\Delta x^1\Delta x^2+\Delta x^1\Delta x^3+\Delta x^2\Delta x^3\right)}^2}\geq \nonumber \\
\geq \left(\frac{\Delta x^1\Delta x^2}{\Delta x^1\Delta x^2+\Delta x^1\Delta x^3+\Delta x^2\Delta x^3}\right)^2 \geq \frac{1}{9}, \qquad\nonumber
\end{eqnarray}
so that
\begin{equation}
c\Delta t \Delta x^1 \Delta x^2 \Delta x^3 \geq \frac{L^{4}_{P}}{3}.
\end{equation}

\section*{Appendix B}
In \cite{3} the condition that no trapped surface is formed is $-\phi<1$, $\phi$ being of course the gravitational potential in the Newtonian approximation. By considering a constant energy density $\rho(-t)$ at negative times $x^0=-t$ over a volume centered at the origin with sides $\Delta x^1+t, \Delta x^2+t, \Delta x^3+t$, the authors obtain $\phi\sim\Delta E\times I$, with
\begin{equation}
I=-\int_{0}^{\infty}\frac{rdr}{(r+\Delta x^1)
(r+\Delta x^2)(r+\Delta x^3)}.
\label{A1}
\end{equation}
Notice that
\begin{equation}
-I=\frac{\Delta x^1\Delta x^2\ln\frac{\Delta x^1}{\Delta x^2}+
\Delta x^1\Delta x^3\ln\frac{\Delta x^3}{\Delta x^1}+
\Delta x^2\Delta x^3\ln\frac{\Delta x^2}{\Delta x^3}}{(\Delta x^1-\Delta x^3)(\Delta x^2-\Delta x^3)(\Delta x^1-\Delta x^2)}.
\label{A3}
\end{equation}
Putting $\Delta A_{DFR}=I^{-2}$, condition (\ref{A1}) becomes
\begin{equation}
{(\Delta E)}^2<\frac{c^8}{G^2}\Delta A_{DFR}.
\label{A2}
\end{equation}
Expression (\ref{A2}) is now comparable (apart from an inessential constant) with our starting condition
(\ref{12}).
Much in the spirit of \cite{3}, we will take $\Delta E$ as given by (\ref{14}) and (\ref{16}).

To begin with, it is easy to see that in the spherical case $\Delta A_{DFR}\sim {(\Delta x^1)}^2$ so that (\ref{A3}) and (\ref{13}) differ only by a positive constant thus giving rise to the same physical consequences.
For $\Delta x^1=\Delta x^2>>\Delta x^3$ (a large disk), the result is $\Delta A_{DFR}\sim
{(\Delta x^1)}^2$ and $\Delta A\sim {(\Delta x^1)}^2$ (where of course $\Delta A$ is given in (\ref{13})), so that in
this case too the two methods agree. However, for a cylindrical geometry with $\Delta x^1>>\Delta x^2\sim\Delta x^3$ we find
$\Delta A_{DFR}\sim\Delta A\sim {(\Delta x^1)}^2$ and
we see that $\Delta A_{DFR}$ is an overestimation compared to our calculations. In a sense, the approximation considered in \cite{3} amounts to identifying a cylinder with the sphere containing it. Of course, a greater $\Delta A_{DFR}$ means a smaller $|\phi|$ so that the preceding overestimation appears to be a consequence of the weak field approximation.

We conclude with the following remark. The fact that the use of the weak field approximation can give sound results should be no surprise. For example, if we take the spherical static metric
\begin{equation}
ds^2=-e^{2\phi(r)}c^2 dt^2+e^{-2\psi(r)}dr^2+r^2d{\Omega}^2,
\label{A4}
\end{equation}
and recall that in the weak approximation $\phi(r)$ becomes the Newtonian potential, we obtain
\begin{equation}
\phi=\ln\sqrt{1-\frac{2GM}{c^2}}\simeq -\frac{GM}{c^2 r}.
\end{equation}
Since (remember that in the weak field approximation $|\phi|<<1$) the condition for no trapped surfaces
becomes $\frac{GM}{c^2 r}<1$, it is wrong only by a factor 2.

\section*{Acknowledgements}
We would like to thank Sergio Doplicher for suggesting the problem and his constant
encouragement, Gerardo Morsella and Nicola Pinamonti for several interesting discussions and suggestions.
LT  would also like to thank
Sebastiano Carpi for many useful hints.
Research by LT has supported by GNAMPA-INDAM and the German Research Foundation (Deutsche Forschungsgemeinschaft (DFG)) through the Institutional Strategy of the University of G\"ottingen.
Finally, we would like to thank the referees for their observations and suggestions.

redpajama_set_name: RedPajamaArXiv


Also known as Taraxacum officinale, the well known yellow Dandelion is considered a weed in most gardens. This plant has actually been an incredible healing and companion plant for centuries. A terrific specimen for anything from skincare products to healthy teas and interesting salads.
All parts of the plant can be used as a natural medication. The most healing properties being in the roots. The plant is high in calcium, iron, vitamins A, B, C and D chlorine, protein, and it is also one of the best sources of natural potassium.
It is a very good natural diuretic, and will hold existing potassium in the system, as well as bring the potassium levels up to normal should they be low in the body. It is one of the best herbs for the liver and as it is a diuretic it can also help to remove toxins and waste matter from the body. It can also help relieve the toxins in the body of rheumatism and arthritis.
A cup of dandelion tea is a wonderful spring tonic to help clean out the body after the heavier foods eaten during the winter months.The milky juice stored in the stem of the plant can be applied to blisters to heal them, and to help take away warts.
A mouth wash can help to strengthen tooth enamel.
Simmer some fresh leaves in a stainless steel or enamel pot with the lid n, for fifteen to twenty minutes. Switch off the heat and allow to come to room temperature. This is when the strengths of the plants are extracted. Put through a plastic strainer and add this water to your bath water as a skin wash for itches and rashes. These leaves cannot be reused, they now belong on the compost heap. It can also be used as a facial wash for pimples and blemishes.
Herb tea. When making a cup of herb tea from fresh or dried leaves, this is called a tisane. If using fresh then the equivalent of two level teaspoons is all that is needed. Or half the quantity of the dried herb. Pouring boiling water straight from the kettle can also interfere with the working and healing properties of the plant. It is far better to boil the water, allow it to stand in the kettle for 2 to 5 minutes, and then pour it over the plant material in the cup. Stir and allow to stand for about two minutes. Then remove the plant. If there are droplets of plant oils floating on top, that means it is possibly too strong, and should be diluted with more water. Milk and sugar are never added to herb teas. Only ever pure honey if a sweetener is required. Then it is very important to sit down comfortably and enjoy your cup of tea. This is when it works the very best.
Use young dandelion leaves in salads.
Harvesting of the root for use is best in autumn after an entire season of growth. The leaves can be harvesting and used fresh or dried throughout the year. It is extremely important to note that no chemicals are to be used in the garden if herb plants are going to be used internally or externally. I use dandelion to make and use natural herbal remedies and also for companion planting. My garden is a haven for the birds, bees, butterflies, lady birds, dragon flies and geckos.
It is also used to make Dandelion wine. It was called lion's tooth in French because of the deeply toothed margins on the leaves.The tap root is large and fleshy with a white interior. The long leaves are lance shaped and deeply indented and form a rosette around the base of the plant. There is a single stem on which the yellow daisy flower appears, on dying off this then forms a puff ball of seeds which are easily spread by the wind. It is a hardy perennial and can reach a height of 600 mm. To use the plant at its best, dig up those growing in the grass and plant in a prepared bed with old compost. Those leaves harvested from amongst the grass will have a more bitter taste This is due to the strong tap root drawing nutrients from its surroundings. The younger leaves are also tastier than the older ones. Dandelion nectar is loved by the bees and also the ladybirds. As the leaves grow so close to the ground this plant is not really attacked by insects. Dandelion requires a nutritional soil and adequate water. This plant is not to be confused with wild thistles. The best identifying factor is that there are no leaves at all growing up the flowering stem.
Gypsies of old used both the roots and the leaves to make a yellow dye.
Dandelion is commonly known as Perdeblom in Afrikaans.
Dandelion belongs to the Compositae plant family.


text:
Q: sed weirdness, unmatched { I'm trying to use the r (read command to append the contents of data2 to data.
I want to append the contents after the line containing 'two'.
I want to delete the line containing 'two'.
But I've hit a brick wall. It feels like a bug, but perhaps it's just my own stupidity.
Ok this command works.
% sed -r '/two/ r /tmp/data2' <  /tmp/data
one
two
five
six
seven
three
four

Sed seems a little finiky about spaces.. Not obvious why, but I'll live with it.
% sed -r '/two/ r /tmp/data2  ' <  /tmp/data
one
two
three
four

My goal is to run a (d) delete after the read command to remove the original line.
This is as far as I get.
% sed -r '/two/{ r /tmp/data2}' <  /tmp/data
sed: -e expression #1, char 0: unmatched `{'

I'm pretty sure that '{' is being matched, it's not the longest command in the world.
What I actually want to run...
% sed -r '/two/{ r /tmp/data2; d }' <  /tmp/data

The system is Ubuntu 12. GNU SED.

A: Break it with multiple '-e' flags, one for each line
% sed -e '/two/{ r /tmp/data2' -e 'd}' <  /tmp/data

A: r /file/path must not have anything after it on its line.
You may find this site helpful as a Command Summary for sed
echo 'one
two
five
six
seven
three
four' >inputfile

echo 'contents of readfile' >readfile

sed  '/two/{r readfile
         d}' inputfile

Note: You can utilize the shell to parameterize sed, by using "double quotes". They enable shell variable expansion. r takes all spaces literally... so don't quote the filename, and don't have any trailing whitespace (whitespace between r and /file/path is ok).
rfile='/tmp/readfile with   multiple spaces in name'
sed  "/two/{r $rfile
       d}" inputfile

output
one
contents of readfile
five
six
seven
three
four

On a side note: There is really no value using < for your input file. Use sed's input file parameter (it keeps things simpler).

redpajama_set_name: RedPajamaStackExchange


text:
Company uses marketing tools from manufacturer
Rob Clark, a lead installer at Affordable Mechanical in Perrysburg, Ohio, services a Coleman Echelon furnace.
Perrysburg, Ohio-based Affordable Mechanical Heating & Cooling switched to Coleman-brand HVAC equipment, and is successfully using the company's business tools.
Rick Montgomery, a 17-year-veteran of the HVAC industry, owns Affordable Mechanical, which sells and services Coleman products throughout northwest Ohio.
Montgomery's wife, Linda, assumes most of the marketing responsibilities for the business, and has been using marketing support from Coleman. Affordable Mechanical is a Coleman Liberties Plus dealer, which provides a variety of services and programs that are designed to help manage their business and meet the needs of customers.
For example, Linda said that Net.Prophet has been particularly useful. The online tool allows participating contractors to download business models and processes, materials, forms and lead-generation systems.
"We 'live' in Net.Prophet," said Linda. "For starters, we're using it to develop the first marketing plan we've ever had by following the steps and advice that Net.Prophet provides to us. Along with that, we're working hard on our leads, learning new ways to generate leads and then track them so that the leads eventually become customers - simple things like asking people who call us how they heard about us and then noting that information. Asking that single question helps us see where leads are coming from and knowing what marketing efforts are working for us."
Linda also said that the company is planning to add a telemarketer to the staff to talk with new and existing customers.
"We have a database of customers and we'd like to be sure they're happy and content so that they'll use us again," she said. "We're also putting a referral program in place that offers discounts to customers who refer us to new customers."
Net.Prophet is also supporting the service side of the business. Rick Montgomery redesigned his installation invoices to make it easier for installers to order products.
"In addition, he's using new service invoices that Net.Prophet recommends," said Linda. "These invoices capture a lot more information from the customer, including information about their existing HVAC equipment, that helps Rick recommend the system or service that best meets the needs of a customer."
He is also using a homeowner questionnaire to gather additional information that will assist him as he prepares proposals for his customers and suggest service.
Other tools available to dealers who represent the Coleman brand include the Build-A-Brochure program, an online resource that allows dealers to customize product brochures. The program enables dealers to tailor content to the specific needs of their customers. The Montgomerys also used the direct mail program and participated in co-op advertising and co-marketing programs.
Affordable Mechanical was the first Coleman dealer to reserve the new Coleman mini display trailer. The 8-foot by 12-foot trailer showcases Coleman HVAC equipment and is available to dealers for consumer events, like mall and home shows.
"It's absolutely beautiful," said Linda. "We took it to the Toledo (Ohio) Home Show in March and watched as it attracted a lot of attention to our booth. We probably collected in the neighborhood of 50 leads at that show and got an immediate sale, thanks in large part to the trailer. We even had our competitors visiting us because they were totally impressed with the trailer. We were absolutely thrilled and are hoping to use it again next year."

redpajama_set_name: RedPajamaCommonCrawl


The parasol or umbrella (Skt. chattra; Tib. gdugs) is a traditional Indian symbol of both protection and royalty. The ability to protect oneself against inclement weather has always, in all cultures, been a status symbol.
In Europe, until a few decades ago, a sunshade was a status symbol for society ladies. In Oriental thought, the fact that it protected the bearer from the scorching heat of the sun was transferred into the religious sphere as a "protection against the heat of defilements." Thus the coolness of its shade symbolizes protection from the heat of suffering, desire, and other spiritually harmful forces.
The dome of the umbrella is held aloft by a vertical handle (just like the mountain upholds the sky), which is identified with the 'axis mundi,' or the central axis upholding the world.
The umbrella is carried above an important dignitary or the image of a deity, to indicate that the person or symbol below the umbrella is in fact the center of the universe, and also its spiritual support. Umbrellas seem to be especially important in processional rites, being like mobile temples. Thus, depictions of the Buddha often display an elaborate and large umbrella above his head.


I had heard mixed reviews about Domino, and I can't say I can do any better. I really wanted to like this movie - I mean, damn, Kiera Knightley with guns! The trailer was sort of misleading, though: she wasn't shooting people nearly enough, and half of the movie was done in that style (which got old REAL quick). And what the hell was that thing with Tom Waits? The action movie suddenly turns into a Jesus movie.
Domino's story is an interesting one, but I don't feel it was told well. Seeing a crappy movie is one thing, but seeing a crappy movie that should have been good is just a disappointment, even is Kiera WAS prancing around with a shotgun.


text:
Kjell is a Scandinavian male given name. In Denmark, the cognate is Kjeld or Keld. The name comes from the Old Norse word kętill, which means "kettle" and probably also "helmet" or perhaps "cauldron". Examples of old spellings or forms are Ketill (Old Norse), Kjætil (Old Swedish) and Ketil (Old Danish). An equally likely meaning is a source, a hope that the boy will get ample resources to draw upon later in life.

Kjell has a name day on July 11 in Norway and July 8 in Sweden, and in Denmark with the variant Kjeld.

Prevalence
In 2007, there were 59,011 men in Sweden with "Kjell" as their first name, making it the 42nd most common masculine name in Sweden. In Swedish and Norwegian it is pronounced with the voiceless alveolo-palatal sibilant fricative [ɕ]. There were 30,809 men in Norway with "Kjell" as their first name. This makes it the 5th most common masculine name in Norway. In Denmark, 8079 men were called "Kjeld" and 5491 "Keld". In Finland, the number of men called Kjell in 2008 was 1405.

The name began to be widely used in the 1600s when it took over from the older name form Kætil or Ketill, which were also precursors of the name Kjetil, and a loan from Latin catillus, which is the diminutive of catinus (= barrel, bowl). Kætil/Ketill was probably one of the most common male names in Old Norse times. In Landnámabók, it is the male name that occurs most often - even more frequently than the most widely used compositions with Tor-. There are 44 found runic inscriptions from the Viking era that contain the name Kætill, which is why it is the 13th most used male name in this material. Five of the inscriptions are found in Denmark and three in Norway, most others have unknown sites. The name was most often written with runes like ᚲᛖᛏᛁᛚ (ketil), ᚲᛁᛏᛁᛚ (kitil) or ᚲᚨᛏᛁᛚ (katil).

In Denmark the name appears in many village (torp) names, so there are nearly 20 places named Kelstrup or Kjelstrup. However, the name does not appear in compositions with -lev, and it can only be explained that it was not used at the time when -lev names were formed. Consequently, we can date the period when Kætil/Ketill was used as a name, at the time between the end of the Migration Period and the beginning of the Viking Age. But the reason that the name gained such tremendous prevalence within a few centuries, we do not know.

The name Kjell is known in Norway from the 1400s. In recent times, the name was widely used in the 1940s and 50s, but is now rarely used for newborn boys.

In Sweden, the name was most popular in the 1940s.

Kjell is today a common name in Norway and Sweden, and Kjeld or Keld is common in Denmark.

The following table provides a detailed overview of the popularity of the male name Kjell and its variants in some of the countries where statistics are available.

Name compositions
Kjell is found in many name compositions, both of the old date, written in one word, or in new ones, which are written in two words.

Female names: Kjellaug, Kjellrun, Kjellfrid, Audkjell, Kjella, Kjellbjørg
Male names: Torkel, Arnkjell, Askjell, Finnkjell, Grimkjell, Hallkjell, Kjellbjørn, Kjellfred, Torkjell
Newer: Kjell Inge, Kjell Magne, Kjell Einar osv.

Kjell is also present in at least one notable Swedish surname: Kjellberg.

People

A–F
Kjell Almskog (born 1941), Norwegian businessman
Kjell Askildsen (1929–2021), Norwegian writer
Kjell Aukrust (1920–2002), Norwegian poet, author and artist
Kjell Bækkelund (1930–2004), Norwegian classical pianist
Kjell Bäckman (1934–2019), Swedish speed skater
Kjell Berg (born 1962), Norwegian curler
Kjell Bergqvist (born 1953), Swedish actor
Kjell Bjartveit (1927–2011), Norwegian physician and politician
Kjell Bohlin (1928–2011), Norwegian politician
Kjell Bondevik (1901–1983), Norwegian politician and uncle of Kjell Magne
Kjell Magne Bondevik (born 1947), former Norwegian prime minister and nephew of Kjell
Kjell Borgen (1939–1996), Norwegian politician
Kjell Carlström (born 1976), Finnish cyclist
Kjell Colding (1931–2009), Norwegian diplomat and politician
Kjell Dahlin (born 1963), Swedish ice hockey player
Kjell Elvis (born 1968), Norwegian Elvis impersonator
Kjell Engebretsen (born 1941), Norwegian politician
Kjell Eriksson (born 1953), Swedish author
Kjell Espmark (1930–2022), Swedish author
Kjell-Olof Feldt (born 1931), Swedish politician
Kjell Fjalsett (born 1952), Norwegian musician
Kjell Fjørtoft (1930–2010), Norwegian journalist and writer

G–M
Kjell Grede (1936–2017), Swedish film director
Kjell Grengmark (1935–2022), Swedish curler
Kjell Håkonsen (1935–2011), Norwegian harness racing coach
Kjell Hallbing (1934–2004), Norwegian author
Kjell Heggelund (1932–2017), Norwegian literary researcher and lecturer
Kjell Helland (born 1940), Norwegian politician
Kjell Henriksen (1938–1996), Norwegian scientist
Kjell Höglund (born 1945), Swedish singer
Kjell Holler (1925–2000), Norwegian politician
Kjell Holmström (1916–1999), Swedish bobsledder
Kjell Hovda (born 1945), Norwegian biathlete
Kjell Isaksson (born 1948), Swedish pole vault world record holder
Kjell Inge Røkke (born 1958), Norwegian investor
Kjell Jennstig (born 1960), Swedish musician
Kjell Johansson (disambiguation), various people
Kjell Jonevret (born 1962), Swedish football manager and former player
Kjell Kaspersen (born 1939), Norwegian footballer
Kjell Koserius (1943–2002), Swedish Air Force major general
Kjell Knudsen (born 1931), Norwegian politician
Kjell Larsson (1943–2002), Swedish politician
Kjell Eugenio Laugerud García (1930–2009), President of Guatemala
Kjell Lauri, Swedish orienteer
Kjell N. Lindgren (born 1973), US astronaut
Kjell Lönnå (1936–2022), Swedish choir leader and composer

N–Z
Kjell Nilsson (born 1949), Swedish weightlifter and actor
Kjell Nordström (born 1949), Swedish politician
Kjell A. Nordström (born 1958), Swedish economist, writer and public speaker
Kjell Olofsson (born 1965), Swedish footballer
Kjell Opseth (1936–2017), Norwegian politician
Kjell Oscarius (born 1943), Swedish curler
Kjell Qvale (1919–2013), Norwegian-American business executive
Kjell Risvik (1941–2021), Norwegian translator
Kjell Rodian (1942–2007), Danish cyclist
Kjell Roos (born 1956), Swedish musician
Kjell Roos Band, a Swedish band led by Roos
Kjell Samuelsson (born 1958), Swedish professional hockey player
Kjell Bloch Sandved (1922–2015), Norwegian author and lecturer
Kjell Scherpen (born 2000), Dutch footballer
Kjell Schneider (born 1976), German beach volleyball player
Kjell Sjöberg (1937–2013), Swedish ski jumper
Kjell Søbak (born 1957), Norwegian biathlete
Kjell-Erik Ståhl (born 1946), Swedish long-distance runner
Kjell Storelid (born 1970), Norwegian speed skater
Kjell Stormoen (1921–2010), Norwegian actor and theatre director
Kjell Storvik (born 1930), Norwegian economist and former Governor of the Central Bank of Norway
Kjell Sundvall (born 1953), Swedish director
Kjell Westö (born 1961), Finnish author

See also
Kell
Ketil
Kjeld
Kjetil
HNoMS Kjell

References

External links
Behind the Name: Kjell
Think Baby Names: Kjell

Norwegian masculine given names
Swedish masculine given names

redpajama_set_name: RedPajamaWikipedia


text:
package org.apache.coheigea.cxf.sts.xacml.common;

import java.net.URL;

import org.apache.cxf.Bus;
import org.apache.cxf.BusFactory;
import org.apache.cxf.bus.spring.SpringBusFactory;
import org.apache.cxf.testutil.common.AbstractBusTestServerBase;

public class STSServer extends AbstractBusTestServerBase {

    public STSServer() {

    }

    protected void run()  {
        URL busFile = STSServer.class.getResource("cxf-sts.xml");
        Bus busLocal = new SpringBusFactory().createBus(busFile);
        BusFactory.setDefaultBus(busLocal);
        setBus(busLocal);

        try {
            new STSServer();
        } catch (Exception e) {
            e.printStackTrace();
        }
    }
}

redpajama_set_name: RedPajamaGithub


With near-perfect proportions and a pure connection to the road, the 4C leaves others in its wake.
Drop the top and experience pure driving bliss.
Driven by the proud racing heritage of Alfa Romeo, the 4C is a high-performance machine unlike any seen on the road.
The turbocharger and pulse converter exhaust manifold are designed to boost torque and respond to every command.
With the four-mode Alfa DNA Pro Drive Mode selector, you can customize your driving experience to suit your needs.
The six-speed automatic Twin Clutch Transmission delivers the instant power of a sequential shift with the convenience of an automatic.
Stronger and lighter than steel, the carbon fiber monocoque chassis further enhances the vehicle's power-to-weight ratio for superior performance.


This simple pair of oval glasses produces a look that is both, intellectual and sophisticated. It is fashionable without being loud. This full pair of metal glasses is the best choice for a formal gathering.


Nestlé Canada's Ice Cream factory attempts world record for the tallest ice cream cone!
To celebrate its 50th anniversary, Nestlé Canada's Ice Cream factory in London, Ontario is trying to set a new world record for the tallest ice cream cone. The cone measures 3.30m high and weighs 640 kilograms. It was produced especially for the opening weekend of the London Western Fair where, as part of the record 11,000 visitors were able to enjoy it.
Over 20 employees from the Ice Cream factory supported by the full factory team as well as four local businesses worked together to bring this exceptional, giant ice cream cone to life. Under the lead of Marc van der Laan and Bonnie Douglas, Project Managers for Nestlé, over 120 hours of work was invested in this world record attempt.
Arthur van Raalte, Director of Factory Operations, London Ice Cream Factory, Nestlé Canada, explains: "It's great to see what you can achieve with both passion and collaboration. We wanted to do something innovative to celebrate the 50th anniversary of our factory in London and the 150th anniversary of Nestlé. The unmatched expertise of our team allowed us to attempt to break the Guinness World record for the tallest ice cream, and we are proud to share the result of our creation with the visitors of the London Western Fair".
The exceptional dimension of the ice cream is not enough for the world record. To be officially validated, the cone needs to be consumed. 11,000 people were able to enjoy a scoop of it during the opening weekend of the London Western Fair (September 10 and 11, 2016) – which Nestlé Canada is an official sponsor.
After its consumption by the public, the Guinness Book representatives will review all details of the operation and officially validate this world record attempt and attribute it to the Nestlé Canada London Ice Cream Factory.
The London Ice Cream factory counts over 500 employees who produce Canada's favourite ice cream and frozen dessert brands, including Real Dairy, Parlour, Häagen-Dazs, Drumsticks and Skinny Cow.
The giant cone was inspired by the Drumstick, a Canadian icon. Nestlé Drumstick is the number one cone brand in Canada. Over 54 million cones are made each year in London, Ontario which, when laid out in a line, would cover the distance across Canada from coast-to-coast 1.5 times.
After years of innovation, Drumstick now comes in a number of formats and over a dozen flavours, from Regular size to King Size and Lil'Drums mini cones, in the original Vanilla to new Sweet 'n Salty Caramel and Chocolate Fudge Brownie.


Taking a look back at another week of news from Cupertino, this week's Apple Loop includes Apple's critical decision over OLED and LCD iPhone displays, a clumsy iPhone design leaks, the cancelled iPhone SE 2, iOS 12 gifts for the iPad, an argument for three new MacBooks, questions over Apple's wireless charging promise, and why President Trump could scupper a trillion-dollar Apple.
Lots of details this week on the size and construction of Apple's new iPhones, which are expected to be announced in early September. First up is the number of LCD and OLED screens ordered, which acts as a signpost towards the product mix of lower- and higher-priced handsets.
Last year's new iPhone mix of the iPhone 8, iPhone 8 Plus and iPhone X include the first OLED-equipped iPhone (in the shape of the X) and two LCD based units (the iPhone 8 family). Tim Cook and his team were counting on a surge of interest in the advanced iPhone X (advanced compared to other iOS devices, I would argue the X simply offered parity with high-end Android-powered smartphones). That super-cycle never appeared, suppliers had orders cut in the quarter following the launch, and while the iPhone X may have broken Apple's internal records, the external evidence points to it falling short of the ambitious targets set by Cupertino.
I suspect that talk of Apple upping the availability of LCD units will simply be Apple reflecting the same sales pattern as last year and ordering parts on that basis, not on the mirage of iPhone X sales it was hoping for.
More on the mix here on Forbes.
Mac Otakara, a site famed for breaking the news Apple would controversially remove the headphone jack from the iPhone 7, has managed to attain dummy units of all three 2018 iPhones [see video below].
…the much praised 'bezel-less' design of the iPhone X (middle) and the massive 6.5-inch iPhone X Plus (right) will not carry over to the cheaper design (left). Instead, the model (which I suspect will simply be called 'iPhone' like the entry level 'iPad'), has uniformly thick bezels. This looks particularly odd on the sides of the device and makes it look like it's in a case. In fact, putting a case on this model is going to make it look even worse.
More about the damage being caused by the big bezels here on Forbes.
The circa 5-inch mini marvel is toast. Instead, the 5.8-inch iPhone X will be complemented by a 6.1-inch budget-friendly iPhone X and 6.5-inch iPhone X Plus. This backs multiple leaks, including my exclusive last month that Apple had decided to drop plans for the so-called iPhone X Mini.
What's New For The iPad in IOS 12?
One of the most talked about areas for the iPad was the new iPhone X inspired gestures including accessing the app switcher, invoking Control Center, jumping between apps, and going to the Home screen.
Photographers are also going to love the improvements to the photo import process, which has remained largely unchanged for years.
Ben Lovejoy and the team at 9to5Mac have been running a serious of discussion articles over the last few weeks under the topic of 'Change My View'. This week, Lovejoy has been taking a look at the moribund MacBook family. He has a suggestion on what is needed, is he right or can you change his mind?
MacBook: entry-level machines at a relatively affordable price; MacBook Exec: the machine that is the current MacBook; ProMacBook Pro: a modern version of the classic, upgradable machines.
Let the polite discussions continue at 9to5Mac.
Apple also wants users to be able to place any of their devices anywhere on the charging mat to begin a charge. That ambitious goal requires the company to pack the AirPower with multiple charging sensors, a process that has proven difficult, the people said. The charger is based on custom charging technology, which it intends to integrate with the Qi charging standard, the company said last year.
The Trump administration told Cook that it would not place tariffs on iPhones, which are assembled entirely in China. That appears to be good news for consumers, but that's not enough to put Apple's worries to rest. Even if Trump doesn't impose tariffs on Apple, China may always decide to take various measures against Apple locally. Apple is the most successful US tech company operating in China, mainly thanks to Cook's leadership, with annual revenues of around $50 billion.
But China could retaliate against Apple in response to Trump's moves. Apple fears that "the Chinese-bureaucracy machine is going to kick in," which could lead to unwanted issues like shipment delays, and increase scrutiny under the guise of national security concerns. China could also attack Apple in response to the way Chinese companies including ZTE and Huawei have been treated in the US recently, the report notes.


A new replacement charger for Toshiba Satellite 19v 3.42a, 65 Watt Power Charger, with power cord included in the package. This Toshiba charger (19v, 3.42a, 65W) works the same as any Toshiba charger requiring 65W or less, as long as the voltage matches. The charger can be used worldwide, so take it with you anywhere you go.


The college experience can leave students rich in knowledge but poor in pockets.
On Nov. 16, California State University trustees voted to raise tuition by 9 percent, increasing annual undergraduate tuition by about $500, bringing the 2012 fall tuition to $5,970. The decision sparked angry protests from students and employees of several public college campuses, including California State University, Sacramento, UC Berkeley and UC Davis.
As the cost of tuition continues to rise, so parallels student loan debts. In 2010, two-thirds of seniors graduated with student loan debts, and owed an average of $25, 250 according to a report by The Institute for College Access and Success. In California, student debt averaged $18,113. These figures are staggering when coupled with the 9.1 percent unemployment rate for young college graduates.
On Oct. 25, President Obama announced additional steps that would make going to college more affordable as well as reduce the burden of federal student loan repayment. The Obama Loan Forgiveness Program is set to go into effect next year. It would affect more than 1.6 million borrowers, and could help to eliminate up to over $100,000 of student loans for eligible graduates.
One component of the recently improved Loan Forgiveness Program would be the reduction of graduates' monthly installment from 15 percent of discretionary income to 10 percent. Additionally, the loan period would be reduced from 25 years to 20 years, with the remainder of the debt to be forgiven by the federal government if payments were made on time each month and without defaulting.
Graduates choosing to opt for public service jobs such as doctors, lawyers and teachers would further benefit with as much as 10 years reduced before loan forgiveness resulting in only 10 years of student loan debt.
There's more good news for Wilson, who is planning on joining the military: Students choosing to serve in the military or volunteer work could have their debts eliminated completely.
Amidst the rising cost of tuition, it's an encouraging sign that President Obama is focused not only on encouraging higher education, but helping graduates manage the cost of it.
To determine whether or not income-based repayment is the right option, visit http://studentaid.ed.gov/ibr.
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PHUKET: The line-up of boats for the 2013 Samui Regatta, set to take place from today to June 1 off Chaweng Beach, features a strong mix of top international racers and regional regatta veterans.
Organized by Regattas Asia, a leading regatta and marine-based sporting event management company in Asia, Samui Regatta is celebrating its 12th year.
Familiar faces on the Asian regatta scene, Frank Pong and Geoff Hill, will be leading the charge with the two largest boats in the fleet – Jelik (75ft) and Antipodes (72ft), respectively. Battling it out with them in IRC Zero will be Sam Chan's TP52 Freefire, a team from the Royal Malaysian Navy sailing their DK47 Uranus and the Aquila Reichel Pugh 45 Katsu, skippered by owner Ben Copley.
In the ever-growing 40-foot fleet, the top contenders are converging on Samui Regatta to battle it out, in this, the final event of the prestigious 2012/13 Asian Yachting Grand Prix Championship.
Competing in IRC One, EFG Bank Mandrake, skippered by Nick Burns is back to defend their title on the well campaigned Mills 40. After losing the title on the final day of last year's regatta, Bill Bremner and crew on Foxy Lady VI are back to make amends, and will be up against Walawala 2, WindSikher, Rikki Tikki Tavi, Elektra, Siren, El Coyote and Dynamite.
"It's great to see such a competitive fleet of boats lining up for the Samui Regatta. Indeed, across all the classes there are some very evenly matched boats and crews and I'm sure all will enjoy the five days of racing we have planned for them," said Simon James, race director.
Having lost out on the IRC Two title by a single point last year, Lennart Fahlgren is back with Amanda and will be racing against Souay 1, Moon Shadow, Phuket favorite Royal Thai Navy 1, and Rolex Sydney Hobart veteran Matt Allen on his Adams 10 Ichiban. With victories at the Phuket King's Cup and Top of the Gulf regattas in the the last 12 months, Ichiban looks the one to beat.
A battle of the SunOdyssey's is set for the Charter class with the SunOdyssey 43 DS Paprika II up against two SunOdyssey 409 2.10 – The Waugh Ship (Ti-Punch), skippered by Barry Waugh and Andaman Sea Pilot, skippered by local regatta veteran Andy Dowden.
With last year's winner of the Multihull class Fantasia unable to defend their title this year, a new winner is set to be crowned from a line-up of some of the region's best multihull sailors. Largest in the class is the Crowther 42 Sonic, skippered by Kirati Assakul who will be up against the well-traveled Corsair 38 Miss Saigon, skippered by David Liddell, Radab Kanjanavanit and his all-Thai crew on Cedar Swan, and locally-built Crazy Horse, skippered by Kunta.
If the winds are blowing, one to watch out for in the Multihulls is Henry Kaye's Seacart 26 Sweet Chariot, which favors the strong winds Samui Regatta is famous for.
"Samui Regatta has become well known for its top quality racing and professional on-water race management, and again this year, the ISAF International Race Officer Ross Chisholm will be calling the shots on-the-water," commented James.
The regatta is equally well known for its onshore social scene, and the beachfront Regatta Tavern, which becomes the focal point in the early evening as the sailors come ashore.
The five days of racing is combined with six nights of parties, including the off-site Beach Republic Party – a mid-week highlight – and the closing Gala Dinner and presentations under the stars hosted by Centara Grand Beach Resort Samui – a fitting finale to the 'Tropical Island Regatta'.