Recent content by sgphysics

To my understanding any quantum system can be describes as a linear combination of eigenstates or eigevectors of any hermetian operator, and that the eigen values represent the observable properties. But how does the system change with time? I suppose big systems with many particles change with...

If you had a universe that only contained a single photon - would it be valid to call it a universe? If so, what properties would it have, like time, no of dimensions etc? And if you added a second photon,could you say that you then have a universe with 2 photons in it?

As you approach the center, less and less mass is added to the already overlying material. Hence the pressure gradient will be at its minimum.

I remember from my physics classes that the wave functions for the hydrogen atoms or an electron in a box showed typical linear wave behaviour. However, when you have a large system's wave function, say for example the universe, will it then show different spatial-dynamic structure? What comes...

I do not share your view on physics, but I shall respect that any forum may decide their own limits. It's not speculation when something can be answered from understanding of math. The number of decimals obtained for c or h measurement is certainly bright engineering, but off-topic. So also the...

Well, actually the model I had in mind was the Schrödinger equation. For a simple system one could easily explore altered solutions from variations in h(bar). So if a universe existed with a different h(bar), perhaps running the same E and V as in our universe, would that be possible? -...

If Planck's constant is changing, how slowly would it need to change before we could observe that something was going on? And if changes were discrete, how large quanta would it take? (for us to observe the jumps) And a follow-up question: If there was another universe here, running a different...

Consider that Earth was placed freely in space, away from the sun. Then another, but similar Earth is brought carefully in contact with it, so that the two planets get locked in place by their mutual gravity fields. Now, would the Earth's suffer a structural collapse, or would they remain more...

Early in the morning it appears to require more force to get out of bed than later in the day, an observation independently confirmed by several people. A possible explanation is a temporal increase in gravity during night/morning, which then is restored to normal level in the day. Hard to...

The OPs question, as I understand iit, is if limit f(x+a)=f(x-a) as a-->0. It is obviously true for a function cont. around x. Always. It is mererly the definition of a continuous function.

It is always true for a function that is continuous around x. You can not say that if it is discontinuous. But sure, you may find examples of discontinuous functions where it also holds.

Is that confirmed by experiments?

What happen if you do the following version of the double slit experiment: In first sequence the right slit is open and the left is closed, and a number of electrons are sent through. Then the right slit is closed and the left is opened, and a new sequece of electrons are fired. After completing...

Would one not need to consider also the change ov momentum of the water insise the bucket? The change d(mv)=mdv+vdm. For a straight bucket the first term is zero, but the second is not. It would counteract the momentum at the outlet, so if the bucket was hanging in a rope, the weight woluld not...

In some cases I have to compare motion measurements on stuctures subjected to irregular loads with simulated data. Because the response is very irregular and fuzzy I can only compare statistical values. The RMS value is such a statistical value, and is the first thing I usually will compare.