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a reply to: delbertlarson

I am not an expert, but from my understanding QED is considered incomplete due to divergences at high energies. It is seen as a low-energy approximation.

Renormalization is done by splitting finite from divergent parts and transforming the divergent parts into renormalization coefficients for mass, charge (making them divergent with increasing energies). To get physical/finite results you replace mass, charge with values you have measured (at some energy).

originally posted by: Arbitrageur

originally posted by: delbertlarson
It turned out that they had assumed the usual special relativity relations to derive the angles rather than measuring them. So it was at that time that I really began to question how many circular arguments might be around right now.

If you're asserting they really had a circular assumption in their calculations I'd be interested in seeing the details of that, but from your vague description it's hard to confirm if that's the case. Maybe they didn't do what you expected them to do but they did what they intended to do. Some experiments test relativity and some don't. If the experiment is testing relativity it should pre-calculate the expected results if relativity is right and what results to expect if some other model is correct instead, or if relativity is wrong. On the other hand, if the experiment isn't testing relativity, it's not unreasonable to make assumptions that relativity is correct based on other experimental results. As long as those assumptions are clearly stated I don't see it as circular or flawed science, even if relativity turns out to be wrong which it probably is in some broader case like Newton's model turned out to be wrong in the broader case.

As I recall (it was about 25 years ago) they were tracking the moon's position. There are some mirrors placed on the moon, that I recall were formed like the interior of three sides of a cube. They were made so that no matter the angles of the incoming light it would be reflected back on itself. And the team was sending light pulses back and forth to the moon. The experiments were very accurate, and the length of travel quite long, so it could have shown evidence for or against length contraction if done to the needed accuracy. But of course they assumed relativity is correct! I think any scientist working in the past 80 years or so does! So I didn't in any way mean they were frauds. In fact, quite the contrary! I, and probably I alone, saw this as a possible test for length contraction. And when I dug into it more I found that they had assumed relativity to set one of the parameters that would have to be measured very accurately to see whether or not length contraction was real. And when I looked into it I couldn't even see how that parameter (the angle of the outgoing light) could be measured accurately enough. So they did nothing fraudulent at all. It just wasn't useful to test relativity.

But the point is that we assume certain truths in science all the time. It is believed that they are tested so thoroughly that we can safely use them as starting points for our advance. Yet sometimes, if you dig deep enough, some (not all) of the tests claimed as evidence assume the theory in their analysis to begin with. Now the original researchers might not make the claim, but subsequent chatter does. Such evidence keeps piling up, and things become "known truth" and then everyone starts from there. It gets harder and harder to see which experiments really do support the theory, and which are simply using it. Everything is consistent, but that doesn't mean that some of the underlying ideas are proven.

In this case, length contraction, it is something that pretty much the entire physics community believes is fully proven. But I maintain it is not. And I don't mean a tweak in the sense you mention that things can be wrong, it is really quite major for our underlying thinking about physics. Yet it is still possible. Now, time dilation and the Lorentz equations are another matter. There the evidence is quite strong. But as for the length contraction, it could go either way. (I am not saying there isn't a length contraction - I really don't know. I am saying more tests are needed.)

So the way things work right now is really not much further along that when it was with Galileo from the point of view of accepting new ideas. At least we no longer use the rack. We just make it very hard for people with different ideas to find work "in science".

That's quite an ordeal, but I guess politics isn't just in politics, it's rampant in corporations, and per to your experience, also in laboratories.

I have six important works now. Length contraction was the first. The others are the ABC Preon Model, a two component aether, ECOFusion, electron cooling to enable a muon collider, and recently, a new relativistic QM. They all ended the same way at the Physical Review. Rejected on spurious grounds. Impugned and summarily judged. A seventh work, on the philosophy of QM, should be prepared, sent in, and rejected in the upcoming year or so. I do delight in informing the editors upon each rejection that I have three sole author PRL's already published, and that while they were happy with my second tier works they won't touch the good stuff.

Of all of them, ECOFusion took by far the most effort, and is most important. So I keep trying to raise awareness, but even the media isn't interested. There are a lot of nuts out there. In fact that was (more or less) the last comment from one of the mods here when my ECOFusion thread was shut down. But it was shut down because I referenced my site and YouTube channel, so I believe it would be a good idea to present my "ECOFusion Saga" on another thread here, and I plan to do that within the next week. ECOFusion could get us off of fossil fuels, and make extra-solar system travel possible. It really is a big deal.

originally posted by: greenreflections


How your interpretations explain Big Bang event?

Thanks

I have never looked into astrophysics nor gravity. Early on I came to the conclusion that we couldn't do controlled tests in that arena and so I believed everything to be mostly speculation. And then, my view was that we inhabit so little of the known universe that speculating on things so far away is just an amusing pastime and not really science. I have tempered those views more recently, since while we can't do a controlled experiment we can gather a lot of evidence, so perhaps things are more amenable to the scientific method than I thought earlier. But in the end I haven't looked into cosmic stuff much at all.

originally posted by: moebius
a reply to: delbertlarson

I am not an expert, but from my understanding QED is considered incomplete due to divergences at high energies. It is seen as a low-energy approximation.

Renormalization is done by splitting finite from divergent parts and transforming the divergent parts into renormalization coefficients for mass, charge (making them divergent with increasing energies). To get physical/finite results you replace mass, charge with values you have measured (at some energy).

Thank you. My gut belief way back when was that the high energy stuff also meant small size stuff and that the whole issue could be resolved with finite sized bodies rather than point-like ones. I will continue my studies.

originally posted by: delbertlarson
But of course they assumed relativity is correct! I think any scientist working in the past 80 years or so does! So I didn't in any way mean they were frauds...

It gets harder and harder to see which experiments really do support the theory, and which are simply using it.

I'm not making a careful observation here based on any research, just a casual observation, than I recall reading numerous articles and papers explicitly stating the experiment or observation was a test of special or general relativity, so for those it was pretty obvious that's what it was. For other works that don't make any such claims, you're probably right that many start with the assumption that relativity is correct. I think most physicists recognize all of our models are seriously flawed in the highest energy realm, and thus know in that realm we need better models. But in lower energy realms where the models work if they are assumed to be correct for other work, I don't see a serious problem with that even if as you say, the assumptions are flawed in a more serious way than just at ultra high energies, because if I thought I could prove that, I think I could get a Nobel prize for doing so, but I don't think I can prove it.

So back to your earlier inference about the possibility of trivial accurate predictions from QED based on circular assumptions, I think you have clarified that the NASA example you mentioned in no way suggests such a trivial circular result and you can dig into QED all you want and I don't think you'll find those precision tests are based on trivial circular assumptions either but you can let us know if you find otherwise. In my experience when I've dug in deeper I usually find that not only have other physicists already thought of what I thought was my novel approach but they've already considered other approaches I didn't even think of.

In this case, length contraction, it is something that pretty much the entire physics community believes is fully proven. But I maintain it is not.

Length contraction is difficult to prove. We can get protons and other tiny things to relativistic speeds, but their dimensions are too small and too difficult to measure to give us clear results on length contraction. For larger objects which would have an easier to measure length contraction, we can't seem to get those to a significant percentage of the speed of light.

I haven't seen any direct proof of length contraction so I'm not sure why you say "the entire physics community believes is fully proven", that's not my impression, though it's just an impression. It seems to me like they have considered both "indirect proof" along with all of the other tests of relativity which can be directly tested to make the inference that it's plausible or even likely that the length contraction part of relativity is also correct, but this falls short of direct proof.

Maybe as experimental techniques advance we can devise better tests which are more direct. I was reading the new ATS thread Sailing to Alpha Centauri about accelerating macro sized probes to relativistic speeds and how recent advances have made this more feasible than ever. So I started wondering if a robotic measuring probe was sent to orbit one of the outer planets, if it might be able to measure length contraction directly on another probe launched from Earth and accelerated using this advancing photonics technology. Someone pointed out the energy consumption of the needed laser array would dwarf that of CERN which spends over a million dollars a month on energy costs, and the robotic measuring probe would probably cost millions, so it's not a cheap experiment but it may be becoming increasingly feasible with advancing technology.

originally posted by: delbertlarson
a reply to: joelr

If we have a point-like electron with charge e, it will have an infinite, positive, self energy from that charge by the classical arguments. If we now let e run to infinity that would naively appear (at least to me) that we have infinity squared, not a cancellation. How does QED refute that logic?

Infinity squared is just infinity. But I know what you mean. The answer might be to follow the mathematical argument.
Understanding the 3 steps - Regularisation - Take a divergent term and put in a finite integral or a cut-off scale, then renormalize combining divergents with tree-level propagator then you remove the cut-off limit.

A non-mathematical way is to say it allows us to mathematically understand low energy physics without having to understand what happens at higher energies.

And further, is QED saying we now have negative infinite energies in order to cancel out the positive ones? For pre-QED physics, total energy is always a positive quantity in any physical system I know of. Of course, in bound states the total energy is less than the total energy of the constituents, but I don't obviously see what is bound here if we are considering a single particle.

No, it's just letting the divergent terms cancel out in a rigorous mathematical way.

I have heard that QED is the most accurate theory ever. My question really is what experiments prove that, and how many free parameters are being determined as a result of those experiments. I believe the claim comes from truly impressive work, both theoretically and experimentally, on g-2 experiments. I understand that such experiments and theory agree to many, many decimal places. But if the bare mass is set via renormalization through these experiments, then these experiments are really just extremely accurate determinations of the physical bare mass constants. That is still excellent and important science, but it doesn't address my question. And charge gets set via renormalization too. So that should allow a perfect match to the Lamb shift through a determination of bare charge, once the bare masses were calculated by g-2. So next we get to high energy scattering and possibly decay processes, and I don't believe we get all that many 9's of accuracy in those measurements. The scattering measurements will require excellent knowledge of energies and momenta both before and after the events, while the decay processes rely on assumptions of internal structure. So that is what I meant by the question.

I think that's right, at higher energies the accuracy goes down.

Proof of time dilation is real on example of muon decay.

cheers))

a reply to: greenreflections
Yes the muon time dilation is well known but unfortunately your source contradicts Einstein's statement that it's momentum that increases with velocity, not mass. I made a thread about that where I agreed with Einstein that we shouldn't be discussing mass increase as your source does. Unfortunately Feynman and some others popularized that idea about mass increase, but it doesn't seem right.

This is a great thread.
Probably a simple question already answered however a few too many pages to sift through.

Anyway here goes...

Are there different forms of time?

To put it in context, if time was created in the big bang then how could whatever changed to create the big bang change without time as a reference point.

originally posted by: Arbitrageur
a reply to: greenreflections
Yes the muon time dilation is well known but unfortunately your source contradicts Einstein's statement that it's momentum that increases with velocity, not mass. I made a thread about that where I agreed with Einstein that we shouldn't be discussing mass increase as your source does. Unfortunately Feynman and some others popularized that idea about mass increase, but it doesn't seem right.

Your right The mass (the true mass!) is an intrinsic property of a body, and it does not depends on the observer's frame of reference. It doesn't change at all but momentum adds force, or you need more force to mI've the object faster. This is where relativistic mass comes in and why many people get confused. A craft traveling at near the speed of light doesn't weigh more than it started a universe where this occurs can't exist. But as you get closer it's relativistic mass increases, basically meaning it takes more force to move thr object just as if the object were heavier. Our craft could eventually require the same enervy it would require to move a planet or a solar system thr closer you get to the speed of light.

a reply to: Krahzeef_Ukhar

No time and dark matter coupled to it existed b4 the big bang imo and it ticked enormously fast

You smarty pants, probably gave up on the Skunk Works, that's why I would like to formally invite you to share your opinion here.

originally posted by: dragonridr
But as you get closer it's relativistic mass increases, basically meaning it takes more force to move thr object just as if the object were heavier.

You're right you can say "as if it was heavier (or more massive)", but according to Einstein it's better to say it takes more force to accelerate it because it has more momentum, and he apparently preferred the concept of "relativistic mass" not be taught.

originally posted by: Krahzeef_Ukhar
Are there different forms of time?

Before Einstein's relativity, many thought that time was absolute, and relativity was a big upset to the old way of thinking when Einstein said time isn't absolute, it depends on where you are and how fast you're moving relative to other objects or something along those lines.

So Mary can see events happening in the order 1, 2, and then 3, and John can see those same events happening in the reverse order if he's in a different reference frame, according to Einstein's theory.

In practice, for those differences to be significant requires either traveling at relativistic speeds (near the speed of light) or being near massive objects like black holes. We have a tiny amount of time dilation on Earth's surface versus the GPS satellites which does end up being significant because of the precision required for GPS, but in most other situations, the way we measure time seems pretty steady outside of precision lab experiments with atomic or optical clocks, and aside from psychological and neurological effects like "a watched pot never boils" and "time flies when you're having fun".

The other "form of time" is that which humans experience, called "perceived time". There is a lot of research on this and it appears that we don't have "internal clocks", but rather our perception of time is influenced by neural activity, which is probably why we have sayings like "time flies when you're having fun". Time itself doesn't move any faster of course, but we can perceive it to move faster (or slower). Humans don't make very good clocks.

originally posted by: Peeple
You smarty pants, probably gave up on the Skunk Works, that's why I would like to formally invite you to share your opinion here.

I'll share it here instead if you don't mind. Looks like your idea has a lot in common with Rupert Sheldrake's ideas, so I'll just re-post the comments made by the editor of a prominent scientific journal (Nature) regarding those:

John Maddox Comments Regarding Rupert Sheldrake's Book:

...Sheldrake's book is a splendid illustration of the widespread public misconception of what science is about. In reality, Sheldrake's argument is in no sense a scientific argument but is an exercise in pseudo-science... Many readers will be left with the impression that Sheldrake has succeeded in finding a place for magic within scientific discussion – and this, indeed, may have been a part of the objective of writing such a book.

a reply to: Arbitrageur

Right. This is an extremely long thread and, obviously, I haven't read all the posts; well, I've actually read about three. So apologies in advance if this question has come up before and been addressed, but here goes.

Why do physicists, on every damn science documentary I watch, keep banging on about how weak gravity is compared to the other forces? And use the same twee example of picking up a paper clip with a fridge magnet while announcing that this is defying the gravitational pull of the whole Earth?

I'm not a physicist (most people aren't) but a lot of lay people are clued up now about gravity's strength being directly proportional to proximity and mass; this does not appear to be the case for the other forces which are the strength they are, regardless of external factors.

So it is not very surprising to such people that, where the values for proximity and/or mass are low, the strength of gravity will be correspondingly weak. And vice versa.

Inside black holes, the magnitude of the gravitational effect is such that it bends and stretches and tears space time. That's pretty strong! Even light (electromagnetism) can't escape it's influence. So, in this example, gravity is more powerful than electromagnetism.

It makes no sense to me to describe gravity as a 'weak' force; it's a relative force, surely?

Please explain this to me.

originally posted by: CJCrawley
Why do physicists, on every damn science documentary I watch, keep banging on about how weak gravity is compared to the other forces? And use the same twee example of picking up a paper clip with a fridge magnet while announcing that this is defying the gravitational pull of the whole Earth?

Think of it on a "per particle" basis, that's what the scientists are talking about. Gravity is something like a trillion trillion trillion times weaker than the electric field, though that's not an exact calculation, it's a rough comparison.

If you say a penny isn't much money, you'd be right. But if you have 100 million pennies you'd be a millionaire, and a million dollars is a lot of money. So gravity can work kind of like that, one proton doesn't have much gravity, but all the protons in the Earth (and other massive particles) added up do have quite an effect. If you keep adding enough mass you eventually get black holes, which as you say is almost incomprehensibly strong, but the gravity of an individual proton is still immeasurably weak using current technology. The interaction of electric fields of individual protons, while still not as strong as the strong force, are much stronger than gravity.

I'm not a physicist (most people aren't) but a lot of lay people are clued up now about gravity's strength being directly proportional to proximity and mass; this does not appear to be the case for the other forces which are the strength they are, regardless of external factors.

This is a partial misunderstanding on your part. Gravity follows the inverse square law. So do electric fields, and magnetic fields would too if we had magnetic monopoles, so they would follow the same proximity effect as gravity. Since we don't have magnetic monopoles (quasi-particles have been compared to magnetic monopoles, but they are not true monopoles), the dipole properties of magnets cause them to follow an inverse cube rather than inverse-square law, so it still changes strength with proximity but at a different rate than gravity.

The strong nuclear force is the oddball that doesn't decrease in strength with increasing distance, like the other three interactions do. It's about 100 trillion trillion trillion times stronger than gravity.

Here's more reading if it might help:

Gravity is Really Weak?

originally posted by: Arbitrageur

originally posted by: Krahzeef_Ukhar
Are there different forms of time?

Before Einstein's relativity, many thought that time was absolute, and relativity was a big upset to the old way of thinking when Einstein said time isn't absolute, it depends on where you are and how fast you're moving relative to other objects or something along those lines.

I get all that, but 14billion yrs ago it started, and as I understand it time is included in that.

Whatever processes were involved in starting that required time as a reference point otherwise nothing could change.

Is that because matter (or at least matter created in our specific big bang) has to follow a concept of time that is different to things like virtual particles?

a reply to: Krahzeef_Ukhar
As mentioned in the last few pages, our models break down at big bang energies, so we really can't model the big bang accurately prior to that point where they break down. So not only can't we say much about time at the beginning of the big bang, but we can only speculate about other aspects of the earliest part of the big bang also.

One of the speculative ideas is the Hartle–Hawking state.

In theoretical physics, the Hartle–Hawking state, named after James Hartle and Stephen Hawking, is a proposal concerning the state of the universe prior to the Planck epoch.

Hartle and Hawking suggest that if we could travel backward in time toward the beginning of the universe, we would note that quite near what might have otherwise been the beginning, time gives way to space such that at first there is only space and no time. Beginnings are entities that have to do with time; because time did not exist before the Big Bang, the concept of a beginning of the universe is meaningless. According to the Hartle–Hawking proposal, the universe has no origin as we would understand it: the universe was a singularity in both space and time, pre-Big Bang. Thus, the Hartle–Hawking state universe has no beginning, but it is not the steady state universe of Hoyle; it simply has no initial boundaries in time nor space.

It sounds like you might be saying this proposal is wrong, and maybe it is, it's only a speculative idea, not a proven theory. We really can't say which of the speculative ideas about the earliest part of the big bang are right at this point until we have better models; they're all speculative.

a reply to: Arbitrageur

No problems. Thanks heaps for that anyway.

I'm not saying it's wrong at all, if anything I'm trying to find out why my question is wrong. I'm just thinking that the various models for what caused the big bang seem to require time to happen.

As spacetime has a starting point I thought there must be virtualtime or quantumtime or something like that which precedes it.

This alternate time would have to be outside our own universe otherwise big bang's could be happening everywhere and it wouldn't be any good. So even if such a thing does exist it would never be provable anyway and we're back to the square one.

I'm really just trying to see if I'm missing the point on something basic here or whether it's just a question that may never be answered.

a reply to: CJCrawley

yes gravity is not a weak force. when you are picking up a paper clip, you are overcoming the gravity of the paperclip actually.
the physicists are working to keep the dogma of GR alive.
I invite you to read the thread in my signature

a reply to: CJCrawley

You can also watch this youtube video, which demonstrates exactly what is going on in Nochzwei's thread...

It will save you the time and mind numbing effect the thread will have on you. Thermal expansion at its noisy Garfield box decal glory.