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Physics grad from top 5 US university, will answer any college level physics/engineering/math/chemistry question that I can.

There's gotta be a few of you who are not done with exams yet!

Which university?

Undergrad at MIT back in the day.

I'll have a go, given our joy at distributed GPU number squashing here.

Subject: Multi-CSF spin and space symmetry-adapted trial waveforms using combinations of determinants.

Of the different methods that are currently in use in trialing the best wavefunction of the form:

ψ = Σ_IC_IΦ_I

where Φ_I is a spin and space adapted configuration state function made of determinants of the form | Φ_I1 Φ_I2.. Φ_IN |

which method (such as MCSCF, CI, MPPT, couple cluster..) is most adaptable and will realize the most gains using distributed computing to determining the CI coefficients and the LCAO-MO coefficients (describing the Φ_Ik. Since all these methods require transforming AO-based electron integrals to mo-based integrals, are there any optimizations that can be done in a distributed method on par and beyond the array transformations that simplify the two-electron integral list transformations with computer time proportional to N⁸ down to an N⁵ time scale?

Also, explain gravity. Elaborate on your answer.

I am not that familiar with the specific algorithms in computational quantum state optimization, but I would imagine that the most efficient distributed method would depend on the symmetry of the Hamiltonian in which you are optimizing.

Is this for a college class? I want to take that class!

Quantum mechanics, from the back of the book that nobody gets to.

This.  I asked a physicist on these forums this before and all I got was a bunch of trolling about how I was an idiot.

I'm not sure what you mean by "explaining gravity", since we still do not really know how it arises. We have excellent models for it (read: general relativity), but it's origin is still one of the big unknowns out there.

I did some reading and it looks like the multi-configurational self-consistent field method suffers from poor convergence, which could be mitigated in a distributed network by each node crunching through the CSF space in parallel, with each node starting from equally spaced (in k-space) reference configuration state functions. The node that reaches the lowest non-pathological energy state wins. No block reward though :'(

Thank you.  That's what I believed to be true, but I've been ridiculed on several occasions by people who don't think past "duh, it's gravity".  We don't know how it arises, but we can observe and predict its effects.

Its actually crazy when you think about it. There are parts of our model for gravity that don't quite add up. For example, the stars in galaxies are moving too fast to be held in by what is our model of gravity, requiring the postulation of dark matter-- but dark matter has never actually been observed and we have no idea what it could be-- only that it has gravitational mass.

I have a theory that gravity isn't constant given mass, but I don't know enough physics to be taken seriously by anyone.

Honestly, this is enough to at least be coherent with your theory. Physics is math in the real world, so it's unlikely the theory would "work", but still, explain anyways. I'd be very interested in reading this mass-independent factor.

I don't know that you will find any observable examples of this hypothesis. Mass can be measured not only by gravity and inertia, but also by energy. Take, for example, the fusion reaction of hydrogen into helium. The particles combine and loose a minute amount of mass, which is released as energy. We can measure the energy release and the corresponding difference in the mass of the new particle through any experiment we can conjure. To assert that something has a given mass but a differing gravity force than that expected would mean that we must obtain a different result from some other method of measurement of a particle's mass, which we don't.

It is solely the realm of philosophy to ponder why mass creates gravity or if there is a graviton particle that communicates the attractive force between masses. Since we live in this universe and it's rules, we cannot observe things that have no postulated method of being observed, hence why physicists start to turn into wacky metaphysical philosophers after too much education.

haha, or bitcoin traders!

It's related to the "law of attraction" and how certain people seem to have what can only be referred to as "gravity".  They grab the attention of young children and calm the minds of adults merely by their presence.  Probably too much hocus-pocus for a real physicist.  I have no idea how this would translate to a mechanism for gravity or celestial motion though.  As you can probably tell, I have very little physics education :P.  And no, I didn't bring this up in the situations where I was ridiculed, but you seem like an open minded individual who will at worst politely dismiss me.

Obviously, mass is the strongest factor in gravitational forces, but perhaps there's another factor that can create gravity without mass.  Or perhaps people who don't have "gravity" simply have some sort of repelling force that counteracts their inherent gravity given by their mass.  As you can probably tell, this is something I haven't thought through much and even if I tried, I don't know enough physics for thinking it thorough to be fruitful.  Or perhaps my theory lies more in the realm of psychology and is just bastardizing the term "gravity".

However, I have heard several mystics claim that the force of gravity is lessening in our universe, but we don't notice since it is happening evenly throughout the universe.  I don't know how they would know this or what the mechanism is, but I find it interesting to ponder.  If it were true, how could we know?

And now that I've thoroughly proved my ignorance, please continue with real math/physics discussion :).

Or people who try to think about physics without enough education ;).

Fucking Magnets, How Do They Work?  ;D

I think you might enjoy this video, and the many others on Khan's website. They are super accessible if you are interested in learning more.

http://www.khanacademy.org/science/physics/v/introduction-to-gravity (http://www.khanacademy.org/science/physics/v/introduction-to-gravity)

Thanks... One thing that's always bugged me: why does the gravity equation use radius squared when electric field calculations use radius cubed?  I was taught the cubed was because it spread out in three dimensions, but doesn't gravity also spread though 3 dimensions?

1. to keep this universe in balance so all matter doesn't collapse into nothingness like all the other universes,
2. because gravity is really the bending of space-time and not a force,
3. because you need some easy force math before we make you learn the quantum chromodynamics Lagrangian,
4. thee flying spaghetti monster designed it that way so that pasta-like strings of matter join together in meatball-shaped clumps in her noodly image.

If you can tell me if the Higgs Boson exists I'll pay you ;)

If I tell you what energy levels it doesn't exist at, you can tell me what Bitcoin amounts you won't pay?
http://cms.web.cern.ch/sites/cms.web.cern.ch/files/field/image/Mu95_CLsOnly_WithExcl.jpg

Electrodynamic force also scales with 1/r2, and it is due to exactly the same effect (spreading out into 3 dimensions) as with gravity. I.e. the total force exerted on a shell around the central potential is the same, regardless of how big that shell is (since the area of a shell is proportional to r^2).

http://en.wikipedia.org/wiki/Coulomb's_law
http://en.wikipedia.org/wiki/Newton's_law_of_universal_gravitation

And no, I'm can't tell you whether or not it exists.

The Higgs boson is the only particle that is part of the "standard model" of particle physics that has never been observed experimentally. This is because its interactions with particles we can observe easily are extremely rare and difficult to measure. One of the goals of the LHC is to confirm its existence experimentally, but many physicists believe it will not achieve its goal (as is alluded to in deepceleron's chart)

The chart shows sigma/sigmaSM, which (I think) is essentially a ratio of the likelihood of that particle existing with the mass (in eV, a unit of mass or energy) on the x-axis. The LHC and Tevatron experiments have excluded the possibility of the Higgs existing with certain ranges of mass, but there is still a window where it could exist. At higher masses, (which are out of the range the LHC can observe), the Higgs could still exist, even if the window area turns out to be excluded as well. Deepceleron, please correct me if I'm wrong about this.

The mass of Higgs is unpredicted, so the Large Hadron Collider (not an "atom smasher", or even a "nucleus smasher") continuously collides a stream of protons together at different energy levels in hopes that the constituent quarks + energy will combine into statistical detection above the background noise that would indicate with a confidence level that one can say a Higgs boson is produced at a particular energy collision indicating its mass. It's like throwing a bowling ball in the air to detect the mass of a mosquito in a swarm of bees, or confirm that mosquitoes don't exist (well, actually, it's nothing like that). All the shaded regions are mass ranges that confidently have been eliminated by colliders, leaving the 115-140 GeV/c² range where there is still little confidence of a result either way.

Ask a physicist why one should exist, he'd probably give you a long list of physics and calculus prerequisites before you can understand the particle physics course.

Decided on some rate guidelines:

High-school level:
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2.0btc/hour for homework help

College level:
0.3btc/question
3.0btc/hour for homework help

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Well look at that... I wonder where I got that r^3 at?

I know, I was just being a smartass ;)