678 reputation
310
bio website dropletsforming.blogspot.com
location England, United Kingdom
age 32
visits member for 3 years, 9 months
seen 21 hours ago

1d
comment How does an electron move around in an orbital? Is it “wave-like” or random?
FYI, calculating the surface within which there is 90% probability is actually quite challenging unless the orbital is really simple and analytic. So usually what is plotted is just an isosurface on which the probability density is at a given figure, because that's much easier.
Aug
5
answered Differences between probability density and expectation value of position
Aug
5
answered What exactly is meant by “observed” when talking about the wave-particle duality?
Jul
23
awarded  Yearling
Jul
23
comment Is speed of light and sound rational or irrational in nature?
Regarding rationality of numbers in measurement, David Z's answer is spot on. If you are trying to grasp whether the universe prefers integers, then yes it does. Things like the resonance frequencies of strings are in strict integral relationships (f, 2f, 3f, 4f). Quantum physics is also based on integers; the idea of quanta itself is that nature is lumpy rather than continuous.
Jul
10
comment Classic home experiments for an 8-year-old child
Exactly. That's one of the things that I feel makes for a good learning experiment; there is space for multiple hypotheses, and people usually get it wrong the first time. I remember being sure it would miss, partly because it seemed impossible to hit it every time. Ping. Clatter. Gasp!
Jul
9
comment Classic home experiments for an 8-year-old child
Yes. The narrative is intended to point out that the gun is pointed directly at Kiki. The usual intuition mistake is to assume that bullets do not fall like any other projectile, or to ignore it. The set-up with the monkey letting go as the gun fires is supplying a separation of the motion vector. Clearly for a real gun to function correctly, its targets must compensate for the motion of the bullet.
Jul
9
comment Would a craft travelling increasingly close to the speed of light appear to be decelerating?
True, and this is the basis of many 'paradox' explanation articles. The question, however, was how it would appear to an observer, not to the traveller. To the observer watching someone accelerate near c, it is still an acceleration. Just because you move at some speed relative to me, it does not change my experience of time.
Jul
8
answered Would a craft travelling increasingly close to the speed of light appear to be decelerating?
Jul
8
answered Classic home experiments for an 8-year-old child
Jul
4
comment Does serving food on a hot plate really keep it warm longer?
Extract from the lab diary: "Trial 1, Apparatus: Roast chicken dinner (plate at 21.3deg), dining table, knife and fork..."
Jul
4
answered Why it is difficult to drink tea with a straw?
Jul
2
awarded  Curious
Jul
1
comment Effective mass of a particle
It can also be anisotropic (for example in Silicon)
Apr
9
comment Force between two charged particles
To clarify, do you have 2 charges (q0 and q1) both on the y axis, separated by distance d1?
Apr
8
comment multibody problem and determinism
I'm not confusing them, they are the same thing. We see from the double slit experiment that making the result deterministic changes the very probabilities of the evolution of the system. I'm probably not explaining it very well. Many worlds just says that the mechanism of multiple states evolving simultaneously is deterministic; i.e. the universe bifurcates at every instant. But it does not give an answer on how or why recombination happens. Yet some prefer it because it takes one of the question marks away (at the cost of adding an infinitely bifurcating universe).
Apr
8
comment multibody problem and determinism
I would say it is generally accepted. As we can only falsify non-determinism (i.e. we cannot prove that something has no cause, only that none has been found), there will always be some who dislike the idea of something unseen deciding whether the cat lives or not. However, unless you are in the field of many-worlds theories and so on, it is immaterial what you believe; the equations give you the non-determinism you will have to deal with. The most broadly accepted interpretation (Copenhagen) is that we do not know what happens in the midst of an interaction, only that it follows our equations
Apr
8
answered Should a polyatomic crystal behave similarly to the bulk of each/either of its constituent elements?
Apr
8
answered multibody problem and determinism
Apr
8
answered How to calculate new air pressure with temperature change?