Leaderboard

In a rocket accelerating at 1g, if you are standing in the top ( nose ) and let go of a ball, does it not drop to the bottom of the rocket ? It gains kinetic from potential energy exactly the same as if you let go at the Earth's surface from the same height as the length of the rocket. EM radiation climbing out of the gravitational well to that height on Earth, will be red-shifted, while EM radiation falling into the gravity well will be blue-shifted. This effect is due to gravitational time dilation; the frequency of the EMR are the reference pulses ( light clock ) that measure the dilation. We can now use the equivalence principle to make the exact same statements about the rocket accelerating at 1g. EMR climbing up the rocket ( towards the nose ) will be red-shifted, while EMR falling to the bottom of the rocket ( towards the tail ) will be blue shifted. This is due to equivalent gravitational time dilation, and the effect is exactly equivalent to the 1g , Earth case. Please point out where you see an error in my thinking, Mordred.

When a rocket is standing on earth the time in the top is going faster that the time at ground/rocket-engine level due to gravitational time-dilation. Using the equivalence principle with the same rocket accelerating in deep space, again an observer in the top will see the time passing by faster in the top then a traveler at rocket-engine level. To me this looks like a contradiction because they both will experience the same acceleration and duration of acceleration! I am confused: how is this possible? What am i missing?

Yeah, basically. Primaries are where a party chooses who will be the flag bearer for them during the general election against the opposing party. So, 20 Democrats threw their hats in the ring trying to get the nomination for presidential candidate. This filtering and selection process occurs in the primaries. Votes occur throughout the country on different date and winners of those elections collect state delegates (larger states tend to have more delegates). It then goes to the nominating convention where the person with the most delegates receives the party nomination. If nobody gets enough delegates to win, it becomes what’s known as a contested convention where it basically turns into a food fight (and hopefully won’t happen this year, but absolutely could). In terms of the general election later, it’s really better when a nominee is chosen sooner so the entire party can get behind them and support them. A longer drawn out primary means the same party is basically infighting and eating their young and decreasing their strength in the upcoming contest against Trump... the only one that really matters in the end. X-posted with Charon

Yes in the primaries the parties essentially vote for their candidate to run for the presidency.

This seems like SUCH a stretch to me... manufactured outrage, really. Schiff was referencing a CBS News report... Here's what he said: https://abcnews.go.com/Politics/democrat-schiffs-head-pike-comment-draws-outrage-gop/story?id=68527054 And you're calling this prejudging and insulting, acting like he called their mother fat and their child ugly... The mind just boggles how perceptions can be so deeply skewed based on the media we consume (please note, I've watched all hearings directly... relying solely on primary sources... the actual events... and am not myself relying on interpretations or summaries from news sources).

Just to add some details to the above. Let's look at how photons contribute to the stress tensor. Due to their momentum photons have a high momentum to pressure relation. Matter often described as dust exerts zero pressure. Pressure in the stress energy tensor is described as flux in a given direction (think of the classical container walls). Gravity is also defined by its flux influence in the same manner as pressure. The pressure terms are the diagonal terms the off diagonal terms being shear stresses. [math]T=\begin{pmatrix}-\rho&0&0&0\\0&p&0&0\\0&0&p&0\\0&0&0&p\end{pmatrix}[/math] The [math]T^{00}[/math] is the mass density in the rest frame. The other diagonal terms describe the flux {pressure} [math]diag T^{xx},T^{yy},T^{zz}[/math] for simplicity. T^00 being the mass density entry. (Trying to keep the above as simple as possible lol). There is quite a bit of math involved to fill in the entries which I won't go into.

GR does not make reference to any concept of mass within the gravitational field equations, it references only \(T^{00}\), which is energy density, as well as \(T^{\alpha 0}\) and \(T^{0 \beta}\), which is momentum density. Note that these are densities. Gravitational self-influences do not explicitly appear in the field equations (they can’t, because the associated quantities are not covariant), but are encoded in the non-linear structure of the equations themselves. In GR, the source of gravity is neither invariant mass, nor relativistic mass, but the stress-energy-momentum tensor. This is a generally covariant object, so when you go into a different frame of reference, the components of the tensor may change, but they will change in such a way that the relationships between these components - and thus the overall tensor - remain the same. So, having relative motion may change how different observers measure individual quantities such as densities, momenta, stresses etc, but it will not change the source term in the gravitational field equations. This is also relevant in vacuum, because distant sources determine vacuum solutions in the form of boundary conditions. So essentially what I am saying is that relative motion between test particle and source has no bearing on the geometry of spacetime due to that source, it only changes how the observer labels events in that same spacetime. This is of course provided that the test particle’s own gravitational influence is negligible (otherwise we have a GR 2-body problem, which is much more complex). Because in the energy-momentum tensor, a change in one component also implies potential changes in all other components. In this example, if momentum density becomes non-zero, then energy density and all other relevant components will also change in such a way as to “compensate” (so to speak) for that change. You are basically just shifting around things within the tensor, without changing the tensor itself. This is wrong, SR says no such thing. In fact, SR is a model of flat Minkowski spacetime, it has nothing to say at all about the gravitational influence of anything.

Her plan tops out at $50K. Anything above that must be personally funded. Perhaps a better question is: Why do so many people keep asking us to address unrealistic and unadvocated circumstances? Or: Why do so many people continue standing in opposition without educating themselves on the actual details being discussed?

Incorrect photons has two measurable polarities in its transverse wavefunction.

The top and bottom of the rocket sitting on Earth remain the same distance away from each other, and as specified feel the same gravitational forces. If you want the rocket in space to have the top and bottom remain the same distance away from each other (in their frames), that's called Born rigidity. If you make the rocket Born rigid, the top and bottom will need to have different rates of acceleration, and different proper acceleration. Then the equivalence principle doesn't apply, at least not to say that the space rocket top and bottom are equivalent to the Earth rocket top and bottom. If you want the equivalence principle to apply, just specify that the top and bottom have the same proper acceleration. Don't worry that the spaceship eventually pulls itself apart, you can't constrain everything how you want. There's no contradictions... could the problem be that the two rockets are necessarily different in some way or another? I think the resolution is that the equivalence principle applies locally. it doesn't say that distant clocks and rulers will be equivalent. (Or I suppose it can be applied to the whole rocket if it were in freefall?)

I don't, I pointed out a different examination that employs proper acceleration. One that the Bells spaceship paradox has been worked out in. The ships and string are just added descriptives. You will find that your redshift relations can be shown through the same transformations.

*than This serves as yet another example of how important availability of education is and how our current system is badly failing even the most talented among us.

Correct. I can be wrong, but i think not this one. If so, please show me how.

How would you feel if you don't get cancer treatment when needed...because your taxes went to pay for someone else's student loans instead, even after you paid off your own? Of course, that assumes there isn't an endless source of money to tap in to...

Why do you think that? There is no difference in gravity like on earth and both observers are experiencing the same acceleration.

All forms of handling and/or storage involve losses. Further solar cannot be directly connected to the grid or mains in general. Most equipment has to be special purpose to use it directly.

If gravity slows down the speed of propagation of both electromagnetic and gravitational waves in the same way, then how does gravity go beyond the event horizon of black holes? Even in the movie interstellar the hero transmits information from a black hole using gravitational waves ))))

Good morning Sam and welcome. Was this a class question to think about? The short answer is that very little if any water is lost. Concrete is made from cement, aggregate (largers stones and sand) and added water. The aggregate usually already contains some water spread over (adsobed onto) the surface of the stones and sand grains, and less water is added to compensate for for this. The mosisture content of the aggregate is continually measured for this purpose. The cement is very dry (anhydrous) but it is made from crystalline rocks (eg limestone) which contain water of crystallisation. Water of crystallisation is water that is incorporated into crystals as they form a solid. This is driven off (by heat) in the manufacturing process of the cement and escapes to the atmousphere. The chemical reactions of the cement and the added water are very complicated but essentially the dry cement powder is recombined with water as water of crystallisation in the new artificial rock that is formed. Excess water percolates to the surface of the freshly mixed concrete as it is worked into place. (Water is of course much less dense than concrete) You can often see pools of water on the top of a concrete 'pour'. Further drying out occurs during the month or so after casting the concrete. The chemical reactions generate heat which increase the drying effect, so much that sometimes the concrete is kept moist on the surface to prevent cracking. So the bottom line is that substantial amounts of excess water is used in the process, but is eventually returned to the environment. The water that is chemically combined with the cement more or less balances the water that was removed in the manufacture of that cement.

This particular group has been together about 1 1/2 years old. But if you don't count insults that are older than two weeks that's fine. We'll pretend they never happened. Didn't mean to nitpick. I apologize for assuming you meant what you said. My intent was to call out your Fox News style of debate. I wouldn't mind it so much if you didn't paint yourself as anti-Trump at the same time as you mischaracterize those who are not pro-Trump. Next time I'll speak more plainly.

Clearly wouldn't fit the bill... Susan Collins and Lisa Murkowsky did: Two of the very few GOP Senators considered candidates to vote with the Dems. And yes, I would agree with them. Your country's better off with more Collins' and Murkowsky's...and less Nadler's and Schiff's. But go ahead and think Nadler and Schiff are taking the high road...simply because they are Democrats. .

I don't agree. Trump has admitted to that in any case. Have the Democrats abused power asking for Trump to be investigated?

No doubt...and then Nadler and Schiff won't be the only ones prejudging and insulting the jury prior to final verdict. (not saying Trump hasn't already started)

Yes, but because the spacecraft is accelerating, it will require energy to move an object from the rear to the front of the craft. Therefore the "gravitational" (due to acceleration) potential at the front must be higher than at the rear, so clocks must run faster. No? I'm not sure why @hu?? thinks there is a contradiction here, though. @MigL has provided a couple of answers that seem to fully explain it, as far as I can see.

There is also the fact that the rocket is not perfectly rigid so the back end, near the engines, will start accelerating before the front. As a result there will always be a small difference in speed.. Which then introduces the problem of simultaneity: how do you define "when" you make measurements in the two positions (does this mean there is always a difference in acceleration, front and back? Dependent on the frame of reference.)

I don't think so. Not necessarily. There are all sorts of reasons why the light might be seen after (or before) the gravitational waves. It depends on the cause of each event.

Your opinion is worthless unless supported by evidence. Especially when it is contradicted by both theory and evidence. What are "heavy neutral electrical particles"? How can they be both neutral and electrical? And what does this have to do with gravitational waves?

The equivalence principle states that uniform acceleration is equivalent to the presence of a uniform gravitational field within the rocket. Any region of spacetime with uniform gravity is in fact flat, it has no curvature. This is why you can derive what happens in this rocket from SR, which is a model of flat Minkowski spacetime. The same is not true for the surface of the Earth - the gravitational field of any central mass is not uniform, but tidal. If you had sensitive enough instruments, you could detect geodesic deviation within the rocket (though the effects would be small, so the field within such a small region is very nearly uniform). So these two scenarios are physically distinguishable, at least in principle, given sensitive enough instruments.

Based on SR, a fast-moving object with a rest mass will become a black hole for an external observer, even if the relativistic increase in mass is not taken into account. It should only become a black hole by relativistically reducing its size when it becomes smaller than the Schwarzschild radius for its invariant mass. It can be explained by the action of a spin field (analogous to a magnetic field for gravity). If two moving charged particles interact, the Coulomb force decreases by a factor of K, where K=1/sqrt(1-v^2/c^2), due to the fact that the Coulomb force is partially compensated by the Lorentz force. In the gravitational interaction formula, this factor K will enter once in the numerator, due to the relativistic increase in mass, the second time in the denominator, due to the action of the spin field, and as a result, it will decrease F=G*m1*m2*K/r^2K=G*m1*m2/r^2

That is not possible. Many apparent paradoxes are resolved by realising this.

LINK DELETED Let's get the message out , anyone that could share my channel thanks. Let's change the world with technology together!