/sci/ - Science & Math

>>9715451
>Doesn't interact with anything much.
>Difficult to detect
Is the soul a neutrino?

>>9685778
Not in any important way.

>>9685152
Such as? The only ones I can think of that don't appear to use circles are simple harmonic motion equations, but they use one dimension of a circle (rather than both width and height) to model it.

>>9685245
Apparently people can't explain this. It's not complex at all- I was taught it at age 12- but anyway...
Direct proportionality is when if you multiply the x value by a certain factor and only allow the y value to change (rather than another constant) the y value gets multiplied by the same factor.
So, let's look at your equations.
Y = k + x is not a direct proportionality, as k + 2x ≠ 2 y (using factor 2, but any works).
Y = kx however is a direct proportionality, as k * 2x = 2kx = 2y.
Y = k + x describes a straight line with gradient 1 that passes through variable y-intercept k.
Y = kx describes a straight line through the origin (i.e. y-intercept = 0) with variable gradient k.

>>9623417
These contributions will only bring the heat death slightly closer. It will still happen in the end though, no pun intended. So the amount of suffering won't increase. It may decrease; fewer people are born and can suffer.

>>9620567
1) Stop looking about on 4chan. You are simply procrastinating.
2) Try and work in one hour intervals with a 5-20 min break between each period. During this time, go to the toilet, get a coffee, whatever, but don't interact with a TV, phone, friend, computer etc. In each period, learn a different topic. Those that you don't like or are not confident with should come first to preserve morale. When you've finished all topics, start again. This will help you commit things to your subconscious and long-term memory.
3) make a plan and STICK TO IT. If you miss some periods, just start IMMEDIATELY on the next one.
Hope this helps.

>>9618366
We agree. I mentioned entropy gradients because they tell you whether a process will occur of its own accord. If you think about the specific scenario, you can then establish whether useful work can be extracted.

>>9618043
Please correct me if I'm wrong, but as far as I can tell from a Google search, electronic band theory describes what happens if proximity to another atom kind of introduces a "new" level, not an electron existing between two levels. Again though, I've never heard of this so I may be wrong.
My understanding is thus: an electron has a wavelength attached to it, its de Broglie wavelength. This has to create standing waves around the nucleus. Obviously, the further from the nucleus the electron is, the faster it has to go to keep from falling in, but also the longer the circumference that the wavelength has to fit in to create a standing wave. And, the higher the speed, the shorter the wavelength. Only those regions where these conditions are all met and a standing wave is formed can there be an electron.
So this electronic band theory means that the attraction to another nearby nucleus can allow an orbit which isn't normally possible. It may be in a new level, but it still can't exist between levels.
I know that it's not a wavelength attached to it as such, rather it is the wave, but hey, that can get confusing.

>>9617713
Hey, I agree with you. You are correct. I'm not arguing with you.

>>9615704
1) It no longer exists, as it's been absorbed.
2)Yes, provided there was also another electron in that first level.
3) Either 2 photons of specific wavelengths, one for the 1-2 jump and then one for the 2-3 jump (in that order) or just one with the sum of the energies of the aforementioned photons. Same way it jumps up one. Not always.
4) I suspect that the jump will not occur unless the level that the electron would jump to is empty, but I'm not sure there.
Some levels can make room for extra electrons: this is what gives sulphur it's eccentric compound forming credentials.
5) Probably.
6) What do you mean? The same thing that happens with every other jump; an electron is kicked up into another energy level and essentially teleports between them.
7) the energy of a photon is determined by E=hf, where E is energy, h is Planck's constant (h=6.67E-34 Js) and f is frequency. This is often rewritten as E=hc/λ, where c= speed of light, 3E+8 m/s and λ=wavelength.
Note) I think you're mainly having problems with the idea that electrons do not exist at all between energy levels. They kind of teleport between them. Thus, the photon that they absorb has to be exactly the right energy, or the jump can't be made.

>>9617353
At least, not possible without putting in more energy than we would get out.

>>9615614
That's what I said. It would take more energy to create the vacuum than you would get out of it.
The key point is that you can do useful work if you have an entropy gradient. Inside the container, very low entropy. Outside the container, high entropy. Getting rid of this entropy gradient releases potentially useful energy, but increases the overall entropy of the system.
Returning to OP, you would need something with even less energy than the lowest possible energy state to extract 0 point energy. (probably) Not possible.

>>9615134
What...?
No. It's a PREDICTION, made in the present, that influences the present or future. Not the future itself.

>>9615623
Good proof, thanks. Had always wondered about that. (At university studying languages; only took physics to a-level, but had and still have a strong interest in wider physics.)
>Low density gas
Yes, I wasn't clear about that. Often a CRT won't contain any gas at all. If it does though, it's usually low density because there's not a lot of it(i.e. Low pressure, low number of molecules.) I made it sound like it was low density because it was helium or neon etc.
About the energy being absorbed, I question that slightly. They are essentially beta minus particles at these speeds, maybe even extremely fast beta minus particles. We know that regular beta minus particles can travel a metre or so in air, so I doubt they'd lose too much energy in a say 30 cm tube. Perhaps they'd be redirected a bit and we'd end up with a fuzzy patch on the screen rather than a dot, but all the energy lost?

>>9614763
No, that's someone making a decision about a probable future (decision made in present) and then (present or future) regulating behaviour accordingly.
Present affects present or present affects future.

>>9612997
Assuming they obey our laws of physics, they would presumably either rip themselves apart due to electric force (a quark is basically a singularity, a point charge so has an unimaginably strong field around it) or crush themselves due to the strong force (which only acts over tiny distances, but when it does is very strong). Maybe the strong force would be the atom's version of gravity, holding it all together, preventing loss of energy...
Also, photons would basically diffract around everything, so the only ones that would behave like our photons would be gamma.
Gravity would have 0 effect at these pathetic masses.

Highly unlikely IMO. If there were, they would hardly be recognizable.

>if there were life forms on these atoms, wouldn't there be a humanitarian crisis at CERN?

>>9613101
>Yank electrons out of metal.
Not incorrect, just a bit vague. If you give an electron enough energy, it can escape the electric field (Remember Potential energy = kQq/r where q = -1.6E-19 C). This can be in the form of a short wavelength photon or by "boiling them off" with thermal energy, as you said. The minimum energy required to remove an electron from the surface of a metal is known as the work function.
This metal is the cathode of a high p.d. circuit, and the anode is usually a plate or funnel with a hole in the centre.The liberated electrons accelerate under this high p.d. and most smack into the anode. Some however get through the hole and come out with a high speed, usually at least 5%c. They continue onwards, and this is the cathode ray.
>Air sucked out.
This is true if they are simply hitting a scintillating screen (e.g. CRT TV's, oscilloscopes), but if you can see the ray travelling, it contains a low-density gas that glows when excited like helium or most of the noble gases.
>So that they move in straight lines
They do this anyway. Electrons in cathode ray tubes move so fast (1E+7-2.99E+8 m/s typically) that by the time they cross a 30 cm tube they only fall (under gravity) by about 1E-16 m. This is smaller than a nucleus, so completely negligible.
The "material which glows" is usually some phosphor compound.
Obviously, putting an electric charge or field exerts a force on the electrons and deviates their path.
A magnetic field does something similar, since the electric and magnetic forces are inexplicably linked (they have the same force carrier, the photon. Why is anyone's guess. They do seem quite separate, so it's unintuitive but correct to say that they are the same force.)

>>9579972
The short answer is it's neither a wave nor a particle, it has properties of both. That might seem like a cop-out answer, but it's an answer nonetheless.

Also, Google things. The answer (or lack of one) is not hard to find. This is most people's first glimpse of QM, so there are plenty of opinions out there.

>>9579635
More specifically, it behaves like a wave as it is travelling but must be emitted and absorbed in discrete packets. Making measurements of "position" also tends to "localize" this wave and make it spread out from that measured position.

>>9579103
No. Einstein said one of his biggest irks was pseudo-scientists telling him they thought they knew what a photon was. The point is, if you can travel alongside one, you don't travel. Time does not pass and you go an infinitely small distance in no time (special relativity). We struggle to define something that exists for no time.
If you travel slightly slower than it, it doesn't matter; it still zips away at 3*10^8 m/s. So it's pretty much impossible to observe.
The question is, does it matter? We know what it does under certain conditions, why should we have to know why? We could dedicate those scientific resources to other more important areas like medicine.

>>9578713
I've always seen it as the wave kind of creates its own medium. A magnetic field collapses, and a changing magnetic field always creates an electric field. An electric field always creates a magnetic field. This magnetic field then collapses as the electric field dies away and it repeats. The only thing the speed depends on is how fast the electric and magnetic signals can transfer themselves (Maxwell's equations about permittivity and permeability of free space).

Regardless, waves are not defined in this way so your question isn't really valid.

>>9484231
To disprove 1 we work harder at proving or failing to prove 2.

>>9484116
The idea is that
F is so small that f basically=0
M is so large that m basically =∞
0/∞=a
a basically=0
From a mathematics perspective, yes there is a tiny acceleration, but then... HA! MATHEMATICIANS!

Was for a different thread, but I think it got archived. Something about atheism and simulation theory.
Anyway,

I used to be an antitheist (one who goes around and publicly denounces and ridicules the idea of god), kind of like Isis but without too many bombs, but have now softened to being an atheist (one who doesn't follow the preachings of any god). My main ground for disbelieving theism is that there is no real proof; theists and priests go about saying, "oh, the proof is all around you" and, "if only your heart were not blind, you would see the proof" and all that scripted rubbish. The simulation theory seems to hold water; quanta for example, like the plank length, could be interpreted as pixels. Of course, that would involve the technology being similar to that of our own.

My second ground is that gods, be they benevolent or malevolent, always seem to be predictable.
The simulation theory could be being done either for research purposes or for the sheer hell of it. So it seems feasible, even probable that we are in a simulation.
Sorry. I know that reduces the amount of meaning your life may have.