Hi guys,
There has been many threads over the last years or so and especially over the last 2 or so weeks discussing relativity.

I just wanted to raize the question how does this benefit our lives. How does relativity, esp lorezian aspects affect our lives. What value is there in calculating length contractions and time dilations. What difference does it all make to what we actually do with our lives?

This may be more a philosophical question but I think it would be silly to expect a thorough answer in the philosophy forum.

The thinking that prompts the question is:

If every moving object is subjected to Lorenzian effects then how does an infinite variable be of any use?

If we take a million objects all travelling at their individual velocities how can we detemine a frame of reference that has any intrinsic value?

Well, first of all atomic clocks and GPS are dependent on relativistic corrections for accuracy. It also accounts for various observed effects, such as the excessive lifetime of mesons in the atmosphere (I forget which ones specifically).

Because we don't move at relativistic speeds, obviously Lorentz contraction and time dilation are going to be much less noticeable than other effects, but SR serves as a bridge to GR, which is, despite what others on the message board may argue, the most widely accepted and accurate account of gravity developed. So SR helps in our understanding of how the universe functions, which, though it may not power your car, is of great value.

It may serve a point to establish which 'relativistic corrections' are referred to in your
post, PhysMachine. They are the gravitational time dilation of General Relativity, not
Special Relativity's velocity-based effects. GPS corrections are also made for varying
atmospheric conditions and densities, somewhat akin to the corrections made on
large astronomical telescopes to produce less atmospheric distortion. The muon
(mesons) lifetimes are a complicated question, but their lifetime is based on their
kinetic energy in particle accelerators. The 'mean lifetime' of 2.2 microseconds is a
somewhat arbitrary average set up years ago, an average 'rest' lifetime for a muon
with a rest mass of, I believe, 106 MeV. I forget off the top of my head, but muons
can be produced in an ultra-slow beam with only a few electron volts up to in the
billions of electron (GeV)volts in accelerators. When accelerated, muons gain energy
from the electric field itself, absorbing the electric energy. More energetic muons
have a longer lifetime than less energetic ones, MUCH longer. SR says the longer
lifetimes are a result of time dilation, but I believe it is related to their energy only,
JMHO.

Well, first of all atomic clocks and GPS are dependent on relativistic corrections for accuracy. It also accounts for various observed effects, such as the excessive lifetime of mesons in the atmosphere (I forget which ones specifically).

Because we don't move at relativistic speeds, obviously Lorentz contraction and time dilation are going to be much less noticeable than other effects, but SR serves as a bridge to GR, which is, despite what others on the message board may argue, the most widely accepted and accurate account of gravity developed. So SR helps in our understanding of how the universe functions, which, though it may not power your car, is of great value.

All this really tells me is that relativity apart from a few relatively minor direct implications is simlpy theoretics and extensions of logic in abstract.

Lorenzian affects are purely conjecture ( extensions of logic to support other aspects) and are limited in their how can I say "immediate value".

This is not to ridicule the value to theoretic physics and I aim not to devalue it.

It's just that I would like to know I guess how lorezian affects if founded actually provide us with anything other than a glorious mind game.

edit: I have tried to delete the above post as I consider it to be inappropriate in composition. I will re-compose it shortly.

>> When accelerated, muons gain energy
from the electric field itself,

yep, all muons created in the Earth's electric field gain energy, a good reason why some muons reach the surface

Just as an aside, the atomic clock creator was adverse to GR.

GR is a theory, like any other, its 'correctness' is well open to doubt.

I guess what I am trying to say is over generalised in my last comment:
It's just that I would like to know I guess how lorezian affects if founded actually provide us with anything other than a glorious mind game.

Maybe I should ask what aspects of relativivty have immediate implications on our physical world?
How has relativity been applied to give us a physical result?

As an aside, how was the famous equation E=mc^2 applied. What were the practical ramifications? ( I can think of some but wish not to asssume I know anything)

I guess that maybe I am talking about Applied physics as different to Theoretical physics.

>>>>GR is a theory, like any other, its 'correctness' is well open to doubt.

of course, though a new theory would have to be even better than gr and just as supported by the evidence. i don't think there are any that come near atm.

:-)

>> i don't think there are any that come near atm.

mmmh, maybe? maybe not !
It is seen that a lot of GR claims can be interpreted by "rational" explanations.

QM and GR are at odds. The QM model of the hydrogen atom has been aclaimed.

IMO, Newtonian mechanics and its application to the Universe is very accurate, even more so with electrodynamic considerations (QM).

Plasma physics is reformatting our view of reality.

IMO GR is an obstruction to a better understanding.

>>>>QM and GR are at odds. The QM model of the hydrogen atom has been aclaimed.

what was the gr model of the hydrogen atom?

>> what was the gr model of the hydrogen atom?

GR principles applied to the observed parameters of the hydrogen atom are contradictory and fail to predict basic features. In short it can't be used.
QM is a more recent theory of electrodynamic matter. Basically the matter we live in, and as I stated earlier, plasm physics is allowing us insight into this 'matter' and its interactions, atomic and macroscopic (planets, suns).

Basically everything is a plasma, especially when adequately electrically charged.
At the time GR was formulated knowledge in these areas was minimal.

IMO, a ground up excercise in re-evaluation is in order.

>>>>GR principles applied to the observed parameters of the hydrogen atom are contradictory and fail to predict basic features. In short it can't be used.

if it can't be used then i guess it wouldn't be, so the question remains as to whether gr needs correcting. i mean if qm describes these things then they are used. can you give some reference that gr is used in these cases?

IMO, a ground up excercise in re-evaluation is in order.
can I ask in your opinion is QM "mature" enough to either discard or intergrate with relativity?

i think qm is one of our most accurate theories.....discard it in favour of what?

Boris I am referring to whether or not the two areas of interest are able to merge in some way or are they unable to do so? And if unable to merge what changes to either would be necessary to complete the picture? ( maybe an impossible question and certainly off topic...hey but what the hell!!)

>> Boris I am referring to whether or not the two areas of interest are able to merge in some way or are they unable to do so?

Special relativity is accurate. Extensions into GR concepts are inaccurate IMO.

>>Special relativity is accurate. Extensions into GR concepts are inaccurate IMO.

Good to see that you have finally read and understood the inticacies of GTR Mr Zarkov.

Which bit specifically do you find (IYO) is "inaccurate"?

PS You still owe me an analysis of the Poynting Vector as used in ESGT!!

macx

The purpose of theortical physics is to understand the universe, because some people want to understand. Providing an immediate societal or personal benefit is not necessarily part of the goal of people who look for theories to describe the universe, or people who learn such theories. This being said, most theoretical physics is eventually of some use. Engineering is largely based on ideas that were once useless theory.

Hi guys,
There has been many threads over the last years or so and especially over the last 2 or so weeks discussing relativity.

I just wanted to raize the question how does this benefit our lives. How does relativity, esp lorezian aspects affect our lives. What value is there in calculating length contractions and time dilations. What difference does it all make to what we actually do with our lives?
The entities that are the bricks of our world are a direct consequence of the world being invariant under Poincare transformation.
Poincare transformation are composed of translations and Lorentz transformations. Because of this, the particles that exist in our world are the integer spin particles and the half integer spin particles. Since, as a result of relativity, the half integer spin particles (also called fermions) are subject to the Pauli Exclusion Principle, you can think intuitively as that matter composed of fermions will have a "volume". Shouldn't our world be invariant under Poincare transformation, matter would behave in a different way.

Also, you certainly know that most of the interractions that we are subject to are electromagnetic interactions. All chemical interactions are based on the atom structure which is of electromagnetic nature. In everyday life, except for the gravitational interaction with the earth, you don't feel the gravitational interaction. Most of what governs our physical world is the em interaction.
The em is predicted in Quantum field theories under the laws of relativity.

So when you ask what are the benefits of relativity in our world. the answer is: almost everything.


This may be more a philosophical question but I think it would be silly to expect a thorough answer in the philosophy forum.

I agree with you


The thinking that prompts the question is:

If every moving object is subjected to Lorenzian effects then how does an infinite variable be of any use?

If we take a million objects all travelling at their individual velocities how can we detemine a frame of reference that has any intrinsic value?
We can't, this is the basis of relativity. There is no prefered reference frame.

Technologically, there would be no nuclear power without relativity. There would be no understanding of nuclear reactions at all. There'd be no nuclear bombs either, but that's a relatively small side effect.

Modern navigation would be far less accurate and reliable without general relativity. Timekeeping in general would be far less advanced than it is, and the applications of accurate time keeping are too many to list in a short post.

Our knowledge of astrophysics and cosmology would be practically in the dark ages without relativity (both special and general). And sending space probes to Saturn? Better forget it.

Our knowledge of the structure of matter and materials science would be greatly impoverished, since various aspects could not be explained or even studied without relativity.

Give me half an hour and I could easily find many more areas where relativity has had a huge impact.

How about medicine?
Do MRI and PET scans rely (directly or indirectly) on relativity?

I would just like to point out that relativity and qm (qft) are very accurate in the domains in which they are supposed to be used to predict things. The inconsistency arises because the fields were not developed in tandem (in fact a lot of the problems in qm is because it was sort of haphazardly thrown together in the early years and we still aren't sure what a lot of the stuff really means) and therefore we shouldn't expect to be able to combine the two theories seemlessly. Eventually a new theory which returns QM on the small scale low energy limit and relativity on the large scale high energy limit will have to be developed, and there are currently several candidates (string theory and loop quantum gravity come to mind).

This is just addressing the few posts about the inadequacy of the theories, not on topic, and I apologize for that.