Physics anyone?

[SignalRecon]

What's the essence of consciousness and why is it infinite?

I meant the energy that is your consciousness doesn't "die" so its infinite. But your consciousness isn't because of what was mentioned up there.

[kay]

This may not make a great deal of sense, but I'll try to explain myself

How do we know that gravity isn't a macroscopic manifestation of typically quantum phenomena?
I've got a simple idea of the sum of charges, for instance, of celestial bodies affecting the pulling or, better yet, curvature we see between them. I kind of don't want to get into the mathematical details, well I don't really know where to start with it, but is it possible, so to speak? Does this idea translate to lesser phenomena?
I'm currently reconsidering this post. I forgot about objects closer to earth, like paper falling to the ground.
Then again, that could be some kind of charge density thing.

Some thoughts.

Where has this been discussed? Anyone know of any research and/or theoretical work on it?

I suggest you look at the various Theories of Everything which seek to harmonise the differing and seemingly completely incompatible theory of relativity with quantum mechanics.

[nowaysj]

Kay what do you think, could there be no rational relationship between the quantum and the macro? Like a circle's circumference to its diameter. Are all these GUT's just attempts at squaring the circle?

[kay]

I think there's definitely a relationship between the quantum world and the macro. It's just something that has not been probed enough because the conventional wisdom of past decades has been that quantum effects cannot exist on a macroscale.

However, there have been recent attempts at demonstrating quantum entanglement at increasingly larger scales. Here's a recent article about a proposed means of testing entanglement of the microscale to the macroscale: http://phys.org/news/2014-04-micro-macr ... s-day.html. I think that lines of enquiry such as these will help us move (somewhat) past the seemingly counterintuitive nature of quantum mechanics.

Edit: Forgot to say, I think one of the issues with GUT theories is that they focus on unifying gravity with all the other known forces, which at the moment can only happen at ultra high energy levels not seen since the birth of the universe. There's been comparatively little work done on understanding/testing the direct relationship between the macroscopic scale and quantum effects, almost because it's considered to be a foregone conclusion (I could be wrong about this mind you).

[titchbit]

I'm writing a term paper on quantum entanglement and quantum teleportation.

From what I've picked up, one of the main reasons why quantum theory and relativity are incompatibility is the CHSH inequality or Bell's Theorem. Quantum entanglement seems to indicate faster-than-light action, which relativity of course says is impossible.

My professor told me that entanglement kind of nullifies quantum effects* when you reach macroscopic scales, the main reason why quantum phenomena* don't have macroscopic effects (usually). If you could isolate systems well enough, it would be possible. But like say two particles* are entangled, and then they're subjected to the rest of the world. They immediately interact with the rest of the world and get entangled with other shit and pretty soon everything is so entangled that the effects of entanglement are basically nullified.

***At least that's the way he put it. I don't really know what "quantum effects" even are tbh or which particles "become entangled" and how that happens but it seems like we're always either talking about the math behind it or about vague terms like entanglement without ever realizing what is actually happening.

[kay]

Can't remember whether I posted this article here, but it seems appropriate at this point: http://phys.org/news/2013-12-creation-e ... mhole.html

And yes, I do spend a stupendous amount of time at work monitoring every article on Phys.org.

[Phigure]

Quantum entanglement seems to indicate faster-than-light action, which relativity of course says is impossible.

not quite, since no actual information is going faster than the speed of light

My professor told me that entanglement kind of nullifies quantum effects* when you reach macroscopic scales, the main reason why quantum phenomena* don't have macroscopic effects (usually). If you could isolate systems well enough, it would be possible. But like say two particles* are entangled, and then they're subjected to the rest of the world. They immediately interact with the rest of the world and get entangled with other shit and pretty soon everything is so entangled that the effects of entanglement are basically nullified.

***At least that's the way he put it. I don't really know what "quantum effects" even are tbh or which particles "become entangled" and how that happens but it seems like we're always either talking about the math behind it or about vague terms like entanglement without ever realizing what is actually happening.

what youre describing is called quantum decoherence


this was an interesting relevant experiment at a university in vienna:
http://www.sciencedaily.com/releases/20 ... 092835.htm

a cloud of gas isolated in a quantum state ended up losing its quantum properties and becoming more classical despite lack of measurement or interference from the outside

[titchbit]

Quantum entanglement seems to indicate faster-than-light action, which relativity of course says is impossible.

not quite, since no actual information is going faster than the speed of light

what then is the fundamental reason the two are incompatible? doesn't the CHSH inequality show that entanglement cannot be explained without acknowledging that some events can happen instantaneously?

[Phigure]

Quantum entanglement seems to indicate faster-than-light action, which relativity of course says is impossible.

not quite, since no actual information is going faster than the speed of light

what then is the fundamental reason the two are incompatible? doesn't the CHSH inequality show that entanglement cannot be explained without acknowledging that some events can happen instantaneously?

bell's theorem and the chsh inequality just mean that you have to give up locality, not necessarily that things travel faster than light. it just means that entangled quantum systems are able to influence each other regardless of the distance between them, which seems counterintuitive from a classical standpoint i guess but in qm theres a lot of weird shit that we've had to come to terms with over the last century.

wikipedia states it pretty decently:

Certain phenomena in quantum mechanics, such as quantum entanglement, might give the superficial impression of allowing communication information faster than light. According to the no-communication theorem these phenomena do not allow true communication; they only let two observers in different locations see the same system simultaneously, without any way of controlling what either sees.

quantum mechanics is not incompatible with special relativity. in fact, they work beautifully together and quantum field theory (ie, the standard model) is basically the direct byproduct of combining the two theories into one framework. the problem lies with combining quantum mechanics and general relativity (ie, gravity), and there's a lot of reasons why tbh

[rickyarbino]

This may not make a great deal of sense, but I'll try to explain myself

How do we know that gravity isn't a macroscopic manifestation of typically quantum phenomena?
I've got a simple idea of the sum of charges, for instance, of celestial bodies affecting the pulling or, better yet, curvature we see between them. I kind of don't want to get into the mathematical details, well I don't really know where to start with it, but is it possible, so to speak? Does this idea translate to lesser phenomena?
I'm currently reconsidering this post. I forgot about objects closer to earth, like paper falling to the ground.
Then again, that could be some kind of charge density thing.

Some thoughts.

Where has this been discussed? Anyone know of any research and/or theoretical work on it?

I suggest you look at the various Theories of Everything which seek to harmonise the differing and seemingly completely incompatible theory of relativity with quantum mechanics.

Thanks, any particular starting points you could recommend?

[kay]

This may not make a great deal of sense, but I'll try to explain myself

How do we know that gravity isn't a macroscopic manifestation of typically quantum phenomena?
I've got a simple idea of the sum of charges, for instance, of celestial bodies affecting the pulling or, better yet, curvature we see between them. I kind of don't want to get into the mathematical details, well I don't really know where to start with it, but is it possible, so to speak? Does this idea translate to lesser phenomena?
I'm currently reconsidering this post. I forgot about objects closer to earth, like paper falling to the ground.
Then again, that could be some kind of charge density thing.

Some thoughts.

Where has this been discussed? Anyone know of any research and/or theoretical work on it?

I suggest you look at the various Theories of Everything which seek to harmonise the differing and seemingly completely incompatible theory of relativity with quantum mechanics.

Thanks, any particular starting points you could recommend?

I think the current flavours of the year are string theory (still) and loop quantum gravity. M-theory also has another suggestion of the origin of gravity but I'm not sure it necessarily deals with the quantum side as much (I could be wrong, not read up on it in a while).

This article may also be relevant: http://phys.org/news/2014-04-road-quantum-gravity.html

[magma]

http://www.bbc.co.uk/news/science-environment-27322166

Aww... my heart broke along with this chap's on Boxing Day 2003. He was exactly what you'd want a British rocket scientist to look and sound like.... like a space age Fred Dibnah.



RIP Professor

[scspkr99]

For those that enjoy science but struggle with the harder stuff this is about the best book I've ever read of its type.

http://www.amazon.co.uk/Quantum-Einstei ... 1848310358

Quantum by Manjit Kumar delivers a narrative on all the main advances in early 20 Century physics, they're all there Einstein, Bohr, Heisenberg, Schrodinger, Born, Rutherford. It's wonderful the delivery does what it needs it gets the science across without forgetting what it's trying to do which is explain it's importance rather than just explaining it.

[Muncey]

^ big up, copped.. £3 on kindle can't go wrong.

[garethom]

Big up scspkr99.

On that note, my girlfriend picked a few of these books up the past week, they seem really good at giving a basic overview of loads of shit. They're pretty meaty for a small sized book, and if you're looking for somewhere to start, or just want a passing knowledge, I can recommend them. Suits my girlfriend, has she has pretty obvious, but undiagnosed, ADD

http://www.amazon.co.uk/Physics-Minutes ... 1782066489

[scspkr99]

Good man, copped.

[garethom]

Meant to add that the other ones we grabbed were the maths & economics ones (I think) and they're just as good.

[scspkr99]

Cheers it's usually the maths where I struggle so I'll definitely be copping that as well

[rickyarbino]

Matter will be created from light within a year, claim scientists

Here's the abstract(?)

The ability to create matter from light is amongst the most striking predictions of quantum electrodynamics. Experimental signatures of this have been reported in the scattering of ultra-relativistic electron beams with laser beams1, 2, intense laser–plasma interactions3 and laser-driven solid target scattering4. However, all such routes involve massive particles. The simplest mechanism by which pure light can be transformed into matter, Breit–Wheeler pair production (γγ′ right arrow e+e−)5, has never been observed in the laboratory. Here, we present the design of a new class of photon–photon collider in which a gamma-ray beam is fired into the high-temperature radiation field of a laser-heated hohlraum. Matching experimental parameters to current-generation facilities, Monte Carlo simulations suggest that this scheme is capable of producing of the order of 105 Breit–Wheeler pairs in a single shot. This would provide the first realization of a pure photon–photon collider, representing the advent of a new type of high-energy physics experiment.

[Phigure]

saw that earlier, definitely interesting but i really can't stand sensationalist titles like that, how much more clickbait does it get than THEY ARE GONNA TURN LIGHT INTO MATTER, HAS SCIENCE GONE TOO FAR?

pair production (γ + γ → e− + e+) happens all the time



there's multiple kinds of pair production processes, it's just the breit-wheeler process for which we don't (or rather now, didn't) have a method of making it happen in a controlled way purely by making photons collide. the abstract mentions this: "Experimental signatures of this have been reported in the scattering of ultra-relativistic electron beams with laser beams, intense laser–plasma interactions, and laser-driven solid target scattering. However, all such routes involve massive particles", ie, these experiments have massive particles that interact to give off photons and then those photons interact to produce pairs in the breit-wheeler process