What does p = mv (momentum) really mean?

[Dale]

I'll have to disagree. I bet neither S.R. nor G.R. would have been discovered with that sort of mindset, just for starters.

Hmm, I don't see the connection. Relativity was not developed to answer "what really is momentum?" As far as I know, anyway.

Yes, but don't forget also that getting buried in pure math or looking at nothing but the math seems to be what those who have never made any of the great discoveries in physics do.

I don't think that anyone is advocating that. A balance is clearly needed, but ignoring or avoiding the math is not balanced and is crippling to understanding of physics. In most threads here lack of math is much more of a problem than excessive math.

 

[sophiecentaur]

I'll have to disagree. I bet neither S.R. nor G.R. would have been discovered with that sort of mindset, just for starters.

SR, GR and all the rest were arrived at by trying to apply 'rules' to observed data. 'Real' Science does not look for 'what things really are'. Science has had its fingers burned too many times to risk statements about 'reality'. If you choose to interpret the present state of knowledge as reality then there's not much of interest left for you in Science. I think it is exactly that "mindset" that allows people to make progress and not the assumption that we are at the end of the road.

 

[sophiecentaur]

Yes, but don't forget also that getting buried in pure math or looking at nothing but the math seems to be what those who have never made any of the great discoveries in physics do.

So you expect to find an ultimate description that doesn't involve any Maths and rigour?
PS I was just listening to BBC Radio 4, to a Science Programme and someone made the comment that most researchers never manage to come up with anything 'really important'. There are just not enough breakthroughs to go round. Most of what your average Joe can expect to contribute is a minor tiffle here or there to produce a very small nudge in the right direction - by scrupulous application of the rules and with great experimental care. 99% perspiration and 1% inspiration, as they say.

 

[porcupine137]

So you expect to find an ultimate description that doesn't involve any Maths and rigour?

Where did I ever remotely say such a thing??

 

[sophiecentaur]

Where did I ever remotely say such a thing??

You seemed, to me, to imply some sort of mutual exclusivity between the two. I would very much doubt that Albert E. arrived at his ideas in the absence of a lot of data and without the Maths being constantly at his side. I know he used to talk in terms of stories and dreams he had but I'd bet that was largely post hoc rationalising, for the sake of an audience and his books.

 

[porcupine137]

Hmm, I don't see the connection. Relativity was not developed to answer "what really is momentum?" As far as I know, anyway.

First, I never said everything has to be based upon the sole question "what is momentum".

Anyway, there was a lot of imagination going on when he came up with S.R. and G.R.

equivalence principle (which actually does, in a way, start getting back to momentum), etc. many have come up with the Unruh effect but just imaging and visualizing various implications. etc. etc.

Thinking about mass can get one to Higgs mechanism, etc.

We are also probably talking a bit at cross purposes. I'm being very loose and you are being very strict.

 

[porcupine137]

You seemed, to me, to imply some sort of mutual exclusivity between the two. I would very much doubt that Albert E. arrived at his ideas in the absence of a lot of data and without the Maths being constantly at his side. I know he used to talk in terms of stories and dreams he had but I'd bet that was largely post hoc rationalising, for the sake of an audience and his books.

Well I definitely never remotely meant to imply a mutual exclusivity between the two, so my mistake if it came across the wrong way. I absolutely, completely do not mean to imply that. I don't remotely agree with that statement at all.

And I'd guarantee that stuff was not all post hoc rationalizing. That's the sort of the stuff that all too many lack and sure they can calculate up a storm and handle every equation with a breeze, but do they come up with the major new ideas very often?

 

[sophiecentaur]

I can see we're not real disagreeing much on this one (as if . . . .!). But, having talked with some very (gobsmackingly) clever people in other fields of study (coding and modulation in communications), I have usually noticed that they tend to arrive at their conclusions as a result of loads of Maths but then the presentation to others has required the use of more metaphor. Fact is that the Maths is such a powerful language for Science that it is bound to play a massive part in any frontier bashing.

 

[russ_watters]

That's the sort of the stuff that all too many lack and sure they can calculate up a storm and handle every equation with a breeze, but do they come up with the major new ideas very often?

Who are "they"? I've never once heard a criticism of a physicist from other physicists that they were too mathematical. On the contrary, the math is the most critical part of developing a new theory.

So the direct answer I would give to your question is: Yes, always.

 

[Dale]

First, I never said everything has to be based upon the sole question "what is momentum".

Anyway, there was a lot of imagination going on when he came up with S.R. and G.R.

Sure, but I don't think that any of it was of the form " what really is ...". In fact, if anything I think his approach was more about taking things at face value rather than trying to uncover some hidden reality. The imagination came in figuring out how seemingly incompatible propositions could be compatible.

I doubt that any of the participants of this thread are opposed to imagination, but just by experience have never seen a valuable outcome from "what really is" questions. I think most of the opposition is simply to the specific form of question.