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What Is Gravity?

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Simply put, the faster a particle gets, the more massive it becomes.

Is that actually correct? For example, if you have an electron travelling at a very high velocity, then does it create a large gravitational field? I had a vague impression that this "mass increases with velocity" thing was really a convenient way of making the relativistic expression for kinetic energy conform with the classical one (E=(mv^2)/2) by absorbing the extra factor in the relativistic expression into the mass m. You can either say that the formula remains the same but the mass changes, or the mass remains the same but you have to use a different formula.

I'm not making an assertion one way or the other here, just displaying my ignorance.

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Why is E=MC2 always assumed to be 100% accurate when something as simple as pi has a seemingly infinite number of decimal places?

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So not proved to be correct.

No physical theory is ever proved to be correct. If you want absolutes then you probably need theologians or philosophers, not physicists.

But QED is so much more correct than 99.99% of other theories, I wouldn't lose sleep over its inaccuracy!

At some point theoretical physicists may come up with a unified theory that can incorporate QED, the SU(2) weak nuclear interaction, QCD (an SU(3) strong nuclear interaction) and a quantized variant of general relativity (quantum gravity). We may find that QED is then only an approximation but of the four fundamental theories its probably the least likely to require modification. Unless we find out electromagnetic fields are finite, photons will remain massless.

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Is that actually correct? For example, if you have an electron travelling at a very high velocity, then does it create a large gravitational field? I had a vague impression that this "mass increases with velocity" thing was really a convenient way of making the relativistic expression for kinetic energy conform with the classical one (E=(mv^2)/2) by absorbing the extra factor in the relativistic expression into the mass m. You can either say that the formula remains the same but the mass changes, or the mass remains the same but you have to use a different formula.

I'm not making an assertion one way or the other here, just displaying my ignorance.

It's a very good question and one that I can't easily answer. There is a question of what we mean by mass. I got this from here

Inertial and gravitational mass

Although inertial mass, passive gravitational mass and active gravitational mass are conceptually distinct, no experiment has ever unambiguously demonstrated any difference between them. In classical mechanics, Newton's third law implies that active and passive gravitational mass must always be identical (or at least proportional), but the classical theory offers no compelling reason why the gravitational mass has to equal the inertial mass. That it does is merely an empirical fact.

Albert Einstein developed his general theory of relativity starting from the assumption that this correspondence between inertial and (passive) gravitational mass is not accidental: that no experiment will ever detect a difference between them (the weak version of the equivalence principle). However, in the resulting theory, gravitation is not a force and thus not subject to Newton's third law, so "the equality of inertial and active gravitational mass [...] remains as puzzling as ever".[7]

As I remember (it's been a while) there is a question if all our terms for 'mass' mean the same thing.

Edit for clarity.Though if it did could we measure it (the gravitational field)? I don't see why not.

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Imagine the maximum speed possible is actually the speed of light plus 1mph. Light would travel 1mph slower than maximum speed because it has a very small amount of mass. E=MC2 could then be changed to E=MC+1mph squared.

This is impossible to prove wrong.

Now where is my Nobel prize?

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More laughs...

Honestly, whilst there are some very good discussions, this is like explaining QE to a dinosaur. I suspect the dinosaur would have realised that his talent lay with the eating and not the discussing.... :rolleyes:

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Quantum physics has shown that particles have free will at times

No Quantum Mechanics has shown that particles can have indeterministic states. That is not the same as free will.

It is a current point of debate that it has recently been shown that if we have free will then elimentary particles must also have free will. This is still contentious.

and offers a clear grounding for how this can develop up to the experience humans have including free will and consciousness. Consciousness is not just an accident, it's a grounding part of the universe, the self-aware universe.

Do you think consciousness is outside of space-time?

I stated that I believe that science is eliminating the supernatural. My user name is Athe - the god of atheists. Why on other would I believe that consciousness was not a natural phenomenon.

There is as yet no evidence to suggest that the universe is self aware. Or that consciousness is in any way required.

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So not proved to be correct.

Indeed - the Popperian principle is that you can only ever disprove - not prove.

Strictly speaking you are right. The photon could have a mass that we have not been able to measure. There is instead an upper bound of between

100,000,000,000,000,000,000 and 1,000,000,000,000,000,000,000,000,000,000,000 times lighter than an electron (depending on which physical phenomenon is measured to establish the mass.) Note that this is an upper bound rather than a mass. It is considerably better than 1 part in a trillion.

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Why is E=MC2 always assumed to be 100% accurate when something as simple as pi has a seemingly infinite number of decimal places?

Firstly E=MC2 is not the full equation, and secondly what on earth do irrational numbers have to do with that?

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Imagine the maximum speed possible is actually the speed of light plus 1mph. Light would travel 1mph slower than maximum speed because it has a very small amount of mass. E=MC2 could then be changed to E=MC+1mph squared.

This is impossible to prove wrong.

Now where is my Nobel prize?

Make a prediction based on your theory. Experimentally demonstrate the prediction.

For instance if the photon has mass then the range of the electrostatic force would decrease faster than the inverse square relationship. Therefore all you need to do is demonstrate that this is the case, and you will indeed get your Nobel prize. Keep in mind that proving that the photon has mass would guarantee the average physicist a name that would live on as long as Newton or Einstein, and so you'll have plenty of competition (ie any physicist would love to show this and many have looked).

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No Quantum Mechanics has shown that particles can have indeterministic states. That is not the same as free will.

It is a current point of debate that it has recently been shown that if we have free will then elimentary particles must also have free will. This is still contentious.

I stated that I believe that science is eliminating the supernatural. My user name is Athe - the god of atheists. Why on other would I believe that consciousness was not a natural phenomenon.

There is as yet no evidence to suggest that the universe is self aware. Or that consciousness is in any way required.

So if not their free will, what determines where the particle finds itself? It chooses as it is not constrained.

The universe is of course self-aware. See that screen you are looking at? You are aware of it, therefore you are part of the self-aware of the universe. Unless you are proposing that we are outside of space-time with out consciousness - which would be an interesting idea.

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So if not their free will, what determines where the particle finds itself? It chooses as it is not constrained.

Being unconstrained is not the same as choosing. There is no consensus either way as yet as to what determines where the particle finds itself. It could simply be random - then there would be no choice.

The universe is of course self-aware. See that screen you are looking at? You are aware of it, therefore you are part of the self-aware of the universe. Unless you are proposing that we are outside of space-time with out consciousness - which would be an interesting idea.

Just because I am aware that does not necessarily lead to the Universe as a whole being self aware. Parts of the Universe are clearly self aware (actually to be precise at least one part - me, I can't prove any more than that) but that does not make the Universe as a whole self aware. For instance parts of the Universe are flammable - that does not make the Universe as a whole flammable.

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Being unconstrained is not the same as choosing. There is no consensus either way as yet as to what determines where the particle finds itself. It could simply be random - then there would be no choice.

God does not play dice. ;) If you are right about it being random, it would be the only example of true randomness in the universe. What makes you think you can assume randomness?

Just because I am aware that does not necessarily lead to the Universe as a whole being self aware. Parts of the Universe are clearly self aware (actually to be precise at least one part - me, I can't prove any more than that) but that does not make the Universe as a whole self aware. For instance parts of the Universe are flammable - that does not make the Universe as a whole flammable.

That's like saying I do not have sight because my foot doesn't have an eye.

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God does not play dice. ;) If you are right about it being random, it would be the only example of true randomness in the universe. What makes you think you can assume randomness?

What about radioactive decay? It is currently impossible to predict when a radioactive atom will decay. Isn't that true randomness?

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What about radioactive decay? It is currently impossible to predict when a radioactive atom will decay. Isn't that true randomness?

Indeed. Radioactive decay is one of many examples that one could use to illustrate the randomness of quantum effects. You know that roughly half of the nuclei in a particular sample will decay in one half-life, but it is impossible to say which nuclei will decay.

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Indeed. Radioactive decay is one of many examples that one could use to illustrate the randomness of quantum effects. You know that roughly half of the nuclei in a particular sample will decay in one half-life, but it is impossible to say which nuclei will decay.

It seems random to us due to a lack of knowledge.

Whereas the particles themselves know full well when they choose to decay.

You've just re-worded the initial problem rather than address anything.

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It seems random to us due to a lack of knowledge.

Whereas the particles themselves know full well when they choose to decay.

You've just re-worded the initial problem rather than address anything.

You can measure randomness. Anyone who has tried to generate (pseudo-)random numbers knows how difficult it is to achieve high quality randomness. Radioactive decay is, statistically speaking, completely random. No-one has ever detected any non-random component, AFAIK.

Your comment about particles knowing when to decay is simply absurd.

Edit: Typo.

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It seems random to us due to a lack of knowledge.

Whereas the particles themselves know full well when they choose to decay.

You've just re-worded the initial problem rather than address anything.

I'm assuming you have an experiment to distinguish between it being 'purely random' and 'particles knowing'. I'd like to hear about it please.

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Guest Skinty

Your comment about particles knowing when to decay is simply absurd.

I'm wondering why anyone even bothers to respond to Pick It Down now. He comes out with many of these types of comments which are just ludicrous and he obviously wants to believe what he wants to believe. It's not that he has a flawed theory based on his limited scientific knowledge and that he will be willing to refine it, instead he has adopted a position of faith based on his limited knowledge. He needs to believe in free will and some form of spirituality.

Don't think of Pick It Down as scientifically minded. Think of him as religiously minded.

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You can measure randomness. Anyone who has tried to generate (pseudo-)random numbers knows how difficult it is to achieve high quality randomness. Radioactive decay is, statistically speaking, completely random. No-one has ever detected any non-random component, AFAIK.

Your comment about particles knowing when to decay is simply absurd.

Edit: Typo.

As I said you've just re-worded the problem.

No-one else on this has come up with a hypothesis as to why a particle finds itself somewhere (or decays whenever) other than to say it just does, and then refer to macro-scale probabilities. instead I've used human experience of our free will and present a coherent picture of how the physics says this could happen. The particles are unconstrained, they have free will where they position themselves and their overall behaviour, like that of humans, can be explain statistically but not the individual choice. Working down from our free will, we can see this is the place where the free will that we have originates. I don't see a better theory doing the rounds.

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Guest X-QUORK

Why is E=MC2 always assumed to be 100% accurate when something as simple as pi has a seemingly infinite number of decimal places?

No disrespect, but either come up with something better, or accept that there are people who know what they're talking about.

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As I said you've just re-worded the problem.

No-one else on this has come up with a hypothesis as to why a particle finds itself somewhere (or decays whenever) other than to say it just does, and then refer to macro-scale probabilities. instead I've used human experience of our free will and present a coherent picture of how the physics says this could happen. The particles are unconstrained, they have free will where they position themselves and their overall behaviour, like that of humans, can be explain statistically but not the individual choice. Working down from our free will, we can see this is the place where the free will that we have originates. I don't see a better theory doing the rounds.

What predictions does your theory make? What experiment would differentiate your new theory from the existing theory?

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What predictions does your theory make? What experiment would differentiate your new theory from the existing theory?

It is explanative rather than predictive. You can't predict choices made under free will/unconstrained conditions.

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It is explanative rather than predictive. You can't predict choices made under free will/unconstrained conditions.

A bit like believing in God then.

Edit : We're at the dawning of a brand new era of faith-based Physics! I'll be sure to burn all my old text books.

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A bit like believing in God then.

Edit : We're at the dawning of a brand new era of faith-based Physics! I'll be sure to burn all my old text books.

The new physics is generally accepted by most to provide more evidence for spirituality due to now knowing their is a mechanism to intervene in the universe within what we know.

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  • 276 Brexit, House prices and Summer 2020

    1. 1. Including the effects Brexit, where do you think average UK house prices will be relative to now in June 2020?


      • down 5% +
      • down 2.5%
      • Even
      • up 2.5%
      • up 5%



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