Quantum Physics

This is what happens- you say something consisting of about 6 words. I ask for some clarification on the meaning of those six words- and that requires indepth explanation bringing in several other concepts that each require their own seperate explanation which then leads to further concepts requiring more explanation- FOR EVER!!!

Maybe it helps if you are farming cranberries or sitting in New York jazz clubs- maybe I should give that a go see if it helps me out understanding this stuff (I think Ill start with the jazz clubs )

Pettytyrant101 wrote:This is what happens- you say something consisting of about 6 words. I ask for some clarification on the meaning of those six words- and that requires indepth explanation bringing in several other concepts that each require their own seperate explanation which then leads to further concepts requiring more explanation- FOR EVER.....]

Exactly!!!!!
See! You did understand!  

The nature of the universe is to have most questions have multiple answers, and each answer lead to multiple new questions.
That's what keeps it interesting.
If it were simple, the universe would be a small, drab, boring place to live.

f it were simple, the universe would be a small, drab, boring place to live.- David

True, but at least then I might have a chance of knowing what the buggery was going on in it.

Why would you want that?
Nobody else ever has ever understood what's going on, and some of them have done alright, haven't they? So why should you be special?

Pascal's sphere.

From my experience sitting in Jazz clubs may not add to understanding, but it's a good way to celebrate understanding something new.

#dontunderstandthisstuff

This is just spectacular, love it, footage pieced together from the 5 year mission of the SDO satellite.
Amazing to think that fiery beauty is sitting out there doing this sort of thing every second and effecting everything living down here at the bottom of this gravity well (watch in HD if possible)

It must have been a jolt for the first solar scientists who saw what was really going on. Our sun is a fiery, pustulating scabrous bitch. Doubt she cares much for the likes of us at all. Beautiful, up until the point you try to comprehend the magnitude of the forces involved. Then it's downright terrifying.

Then it's downright terrifying.- Halfwise

Thats where the sense of sheer awe takes over for me.

so what exactly is gravity then? is it a wave or a particle or is it made out of booze?

Being that both booze and gravity drag you down, Occam's Razor suggests they are one and the same.


but for a more scientific answer, most would be happiest calling gravity something that curves space, causing stuff to be deflected as though there was a force on it (Einstein's General Relativity model).  Attempting to explain gravity as particles hasn't worked out so well as yet.

Explaining the effects of gravity as due to the curvature of space isn't so easy, it requires first understanding stuff like changes to length and time caused by relative motion (special relativity), then you link it to the accelerations caused by gravity.  Though Einstein showed quite a bit of talent before General Relativity, this final achievement was a masterwork that even most physicists can't honestly claim to fully understand (they all have the background conceptual tools, just not the training).  I'd love to have the time to learn it, but all I can do is sketch out the basic concepts, and I'm not sure I have all of those quite right.

but is there gravity only on a planet with an atmosphere? oh hang on the moon doesn't have an atmosphere.

Is it not just the name we give to the effect on space time of mass?

Yes.  But how do you use that curvature to figure things out? I can use Newtonian gravity to calculate orbits and stuff, but even though I can say "gravity is the curvature of space" I can't use that knowledge to sit down and calculate an orbit. That takes some training I don't have.

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Gravity and mass are fundamentally linked. You, my dear Figgy, exert a gravitational pull on every other bit of mass around you.  Your reach even extends to me, theoretically, but no instrument would pull that signal out of all the background noise.

Fun fact about gravity: you pull upwards on the earth just as strongly as the earth pulls downwards on you.  Don't believe it?  See if you can follow this logic:

If the earth was the same mass as a Figg, you and the earth would obviously exert the same force on each other.

If the earth was the mass of two Figgs, each Figg separately pulls on you (a force of two), but you pull separately on each of those.  So the force you exert on an object twice as big is twice as much.

Continue this argument up to the gazillion Figgs that would make up the mass of the earth, and you are pulling upward on the earth as hard as it pulls down on you.

It must be so, because when you jump, you push the earth away.  As you fall back to earth, it falls back to you, so you end up at the same place.  Since the earth is so large we don't notice the small amount it pushes away from you: the same push on a small and large objects will not have the same effect (try throwing your cat as opposed to throwing your husband with the same amount of strength).

all I got from that is a few random words insinuating my arse is as large as a mass of cats.

and pulling and jumping. call me old fashioned but that ain't science that's a night out in Glasgow.

but srsly. does gravity exist in the physical world as a thing made of stuff or is it only a concept made up to explain the action of said stuff. just wondering what its made of.

all I got from that is a few random words insinuating my arse is as large as a mass of cats.- Mrs Figg

And all i got out of it is that there is a way to get two Figgs to pull on me!


'does gravity exist in the physical world as a thing made of stuff '- Figg

I thnk its just the name describing an effect rather than a thing like light.

Pettytyrant101 wrote:

'does gravity exist in the physical world as a thing made of stuff '- Figg

I thnk its just the name describing an effect rather than a thing like light.

Yep, though if gravitons exist (gravity particle) then you might talk about things rather than just effect. But nobody's been able to merge curvature of space with particles and come up with something mathematically consistent. They sort of have with superstrings, but end up with a whole plethora of possibilities, none of which seems to be distinguishable by experiment.

I hate gravity, it's always holding you down.

Gravitons. I like that, it sounds like 1950s B movie aliens

We also have neutrinos, photons, bosons, mesons, quarks, leptons....

And those we pretty much know exist. Gravitons not so sure, but probably.

But if gravity is just a word describing an effect how can it have gravitons? Is that not like expecting to find the particles which make up darkness?
Is it not just a language thing- the language treats dark and gravity as if they are physically existing things equal to say light or mass, when they are not?

This is why gravity has remained separate from electromagnetism, the strong and weak force, all of which has successfully be described by particles. Gravity was first described by Einstein as the curvature of space-time in response to mass (as well as the way particle trajectories responded to that curvature). This description was so beautiful and described so much with great conceptual simplicity that nobody is really willing to abandon it.

Except that everything else is described by particles swapping back and forth (though not the kind you might think: they are 'virtual' particles that kind of sniff out all the possibilities and sum together probabilities as waves: see the earlier parts of this thread). So gravity stands alone from everything else.

Maybe it's just the way things are, but people would rather all forces are described the same way. So far, it hasn't quite worked. Maybe the universe is a duality of gravity and everything else rather than a unified theory. I'd be comfortable with that, but I already admit I don't completely understand the depths of either particle theory or gravity. Perhaps if I did, I'd be bothered that they are so different.

I was wondering, is there gravity in space, well the spaces between things like planets? I presume there is massive gravity in black holes and when stars explode, and between objects like planets and their moons etc,  but in the dark stuff in between is there gravity, and if not why not. I suppose gravity hangs round physical objects as they bend thingie mass? is gravity dark energy? how come gravity suddenly stops when you get into orbit? I feel like a 6 year old going why why why.