[ 3 / biz / cgl / ck / diy / fa / ic / jp / lit / sci / vr / vt ] [ index / top / reports ] [ become a patron ] [ status ]
2023-11: Warosu is now out of extended maintenance.

/sci/ - Science & Math


View post   

File: 696 KB, 1269x960, 1402865135896.jpg [View same] [iqdb] [saucenao] [google]
6593510 No.6593510[DELETED]  [Reply] [Original]

Are the laws of physics the explanation to the way energy/matter behave?

OR

The instructions certain energy/matter follow?

>> No.6593516

>>6593510
The first.

>> No.6593538

>>6593516
How does it know to behave that way?

>> No.6593543

they're an approximation of the way energy/matter behaves.

Though if if they were totally accurate their would be no difference.

>> No.6593555

>>6593538
How should we know?

>> No.6593566

>>6593538
it moves.
we measure.
we theorize.

matter/energy don't have knowledge.

>> No.6593570

What is keeping it in check from deviating from the laws? Why is it allowed to move in the first place? What determined that?

>> No.6593573

>>6593570
How should we know?

>> No.6593575

>>6593570
physics does not answer why, it answers how

>> No.6593576

>>6593573
Because Science!

>> No.6593578

>>6593576
Science answers how, not philosophical why.

>> No.6593581

>>6593578
Let me rephrase

How is keeping it in check from deviating from the laws? How is it allowed to move in the first place? How determined that?

>> No.6593594

>>6593581
How should we know that?

>> No.6593597

>>6593594
Isn't science looking into it?

>> No.6593605
File: 166 KB, 523x720, they-dont-think-it-be-like-it-is-but-it-do.jpg [View same] [iqdb] [saucenao] [google]
6593605

How it be like it is?

How it do?

>> No.6593612

>>6593597
Not really. How would we find such a thing out?

If you want current research in this field, contact your local philosopher or church.

>> No.6593654

>>6593566
>matter/energy don't have knowledge.
We're matter and energy and we have knowledge.

>> No.6593662

>>6593654
I actually kek'd.

Religion just can't into any argument.

>> No.6593950

How do you differentiate a physicist from an engineer?

An engineer thinks his math is an approximation of reality.

A physicist thinks reality is an approximation to his math

>> No.6594052

>>6593570
mathematical rules.

basically logic.

>> No.6594062

>>6593654
>evidence show only 0.0000000000000000000000000000000000007% of the mass in the visible universe is aware of its surroundings.
>Therefore my point that matter have knowledge is justified.

>> No.6594679

Matter doesn't even follow set unbreakable rules. We live in a probabilistic universe, so those rules are more like...guidelines, guidelines that map directly to the largest chunk of probable action. The next question is what makes those probabilities the way they are? The answer is mass, or more properly, speed. It's very hard for objects to stand still in this universe.

>> No.6596078

>>6594679
probabilistic is a pseudoconcept.

A particle's spin is probabilistic when measured, but is conserved 100%. probabilistic implies that conservation is also probabilistic, but experimentation shows that's false.

>> No.6596096

neither

The laws of physics are just a mathematical description of the behavior of the universe.

>> No.6596106

Do the current laws of physics predict the emergence of life?

>> No.6596109

>>6593654
No, we are a complex system made of matter and energy and we have knowledge.

You can found simple systems that have memory though, its called hysteresis.

>> No.6596119

>>6596106
I supposed they could, but we are currently unable to prove it. Our laws get to complicated when it come to describing complex systems such as cells, even proteins are hard as fuck to describe accurately, that's why protein folding programs exist.

>> No.6597074

>>6596078

I immediately disagree. Please educate me.

>> No.6597088

>>6593510
>butterface

>> No.6597124

>>6597088
I know right,

>> No.6597205

>>6596106
They probably do, but life is a big complicated and hard-to-define concept, so it's not clear how you'd go about even defining "life", let alone proving its emergence is or is not highly probable based on fundamental physics.

>> No.6597237

>>6596078

Angular momentum is conserved because of Noether's theorem, and spin is a consequence of the Dirac equation. Neither exclude the probabilistic nature of quantum mechanics quantified in the Heisenberg uncertainty relation.

Probability is one of the most foundational and important concepts in statistical mechanics (the behavior of large numbers of particles), and the states that are accessible to a system at a given temperature.

>> No.6597253

>>6597237
>spin is a consequence of the Dirac equation.
wat

The Dirac eqn doesn't "cause" spin. And even then, that's only for electrons.

Particles have spins according to what representation of the Lorentz group their fields transform under.

>> No.6597262

>>6597253

You're right, it's only for spin 1/2 particles. But it does demonstrate that spin is an emergent property of governing differential equations which the theory of Lie groups states precisely, and is generalized for all particles under the Lorentz group.

>> No.6597268

>>6597262
>spin is an emergent property of governing differential equations
well, no.

All of the irreducible, finite-dimensional, unitary representations of the Lorentz group are already known.
These representations are what give particles their spin.

It's only when we use the "quantum fields" formalism that the differential equations for the fields arise from the representation theory.

>> No.6597279

>>6597268

I think we're understanding the same thing from two different perspectives. The Lorentz group is indeed a Lie group, and a Lie group does indeed express symmetries of the solution of a particular differential equation. I think it is probably the same as saying that there are many equivalent representations of physical facts; for instance, the matrix mechanics formulation and Schrödinger equation formulation of non-relativistic quantum mechanics. But I don't doubt that your knowledge of how the problem is expressed in terms of group theory is correct.

>> No.6597300

>>6597279

But what you should understand is that even if we DIDN'T use the fields formalism, and there were NO differential equations, particles would STILL be guaranteed to have spin because of their Lorentz group representations.

>> No.6597313

>>6597300

If our quantum state is indistinguishable from the vacuum then what good is an underlying notion of particle spin? Spin's existence having a tangible outcome necessitates the existence of particles, which are described by wavefunctions and governing differential equations. A field implies the existence of particles in the vacuum, which may then have spin according to the symmetries of the Lorentz group.

In short, I think you're saying spin is "more fundamental" than particle wavefunctions, but I see no reason to accept such a premise.

>> No.6597318

>>6597313

...do you even know why we have the fields formalism in the first place?
Basically, it is so that the scattering matrix will be local and Lorentz invariant.

If we focused on a single relativistic particle, we wouldn't need to invoke the fields formalism at all.

But the particle would STILL have spin, according to which representation of the Lorentz group it is in. Instead of quantum fields, we would simply have a finite-dimensional Hilbert space.

>> No.6597340

>>6597318

>If we focused on a single relativistic particle, we wouldn't need to invoke the fields formalism at all.

I disagree. Creating even a single electron into a vacuum state necessitates virtual photons in the surrounding space to quantize the resulting electric field. Besides, having a single particle state (whether boson or fermion) STILL implies the existence of a wavefunction consistent with a governing differential equation.

Now that we've clarified, I agree the fields formalism is entirely spurious to my underlying thesis, which is that the differential equations of physics are precisely as fundamental as a formulation of spacetime symmetries under the Lorentz group.

That being said, my statement that the Dirac equation causes spin is misleading and not general for all particles.

Thank you for the enlightening discussion, friend. It was a true pleasure.

>> No.6597353

>>6597340
>I disagree. Creating even a single electron into a vacuum state necessitates virtual photons in the surrounding space
I was talking about the low-energy limit, in which we can ignore fluctuations in the particle number.

After all, isn't this what we do in elementary quantum mechanics, which has succcessfully predicted the structure of the hydrogen atom quite accurately?

But I see your point.

>> No.6597361

>>6597353

You are right. And I have seen the s-wave approximation but not in terms of quantum field theory. I still need to learn all of this theory about Feynman diagrams and the Dyson series and how particle physics is most generally formulated.

>> No.6597362

>>6597361
If I may make a suggestion,

take a look at Weinberg's The Quantum Theory of Fields (volume 1).
It's probably the best introduction to the subject, and it's not "handwavy" like most physics textbooks tend to be.

>> No.6597363

>>6594062
huh?

Why is an introductory question - and ultimately something physics won't be able to answer. It's kind of impossible to actually interpret meaning from the math that describes nature.

>> No.6597370

>>6597268
Can you explain how it is that the irreducible lorentz group representation are what give particles their spin?

>> No.6597400

>>6597088

I'd still hit it

>> No.6597402

>>6593510
Neither, they are systems we've made up to catalog our observations of energy and matter. The physical laws don't exist in any real sense, they only compress many observations into a few equations.

>> No.6597437

>>6597402
Well can these "laws" change?

What is keeping them consistent?

>> No.6597466

>>6597437
the observations we are aking still conform to the laws. if the observations change the laws will change

>> No.6597637

>>6597437
>>6597466
That's called the scientific method.

>> No.6597644

jesus christ i need sauce on OP, google has nothing