Recent content by Spinnor
-
Undergrad Textbook description of R##\ddot{\text o}##mer's light speed calculation
Thinking about the data is what feels important to me. Lag is small at first because the separation changes slowly at first. Daily lag increase becomes roughly constant after about a quarter year and then lag reaches a maximum when the Earth is at its farthest from Jupiter. Setting the orbit to...- Spinnor
- Post #23
- Forum: Classical Physics
-
Undergrad Textbook description of R##\ddot{\text o}##mer's light speed calculation
Let the period be 2 days and take measurements for half a year. In that time Jupiter moved roughly 1/24 an orbit so in the half year we let Jupiter be approximately stationary. If the closest emergence was at midnight then a half a year later the Earth would be approximately the Earth's orbital...- Spinnor
- Post #21
- Forum: Classical Physics
-
Undergrad Textbook description of R##\ddot{\text o}##mer's light speed calculation
Maybe it would be helpful to produce an imaginary data set. Let Io make one complete orbit in a nice round number, say 1 day or one week (as measured at closest approach) and when Earth and Jupeter are at closest approach, emergence occurs at exactly midnight? What is important is the data set...- Spinnor
- Post #19
- Forum: Classical Physics
-
Undergrad Edge of Brillouin zone,1D crystal, graphene, standing wave, band gap
That is one of the first things you learn when you study the physics of graphene. A standing wave in graphene is a bit more complicated. I am not sure if you answered my question though, "Can the standing probability wave be shifted forward or backward in the direction of the momentum vectors...- Spinnor
- Post #3
- Forum: Atomic and Condensed Matter
-
Undergrad Edge of Brillouin zone,1D crystal, graphene, standing wave, band gap
Consider the standing wave of probability at the edge of the first Brillouin zone in a 1D crystal for an electron, first figure b below, which gives rise to a band gap, It is clear from the first figure b where we get the gap in energy, for an electron more likely near the ion cores, lower...- Spinnor
- Thread
- Replies: 2
- Forum: Atomic and Condensed Matter
-
Graduate Universal quantum physics
In your paper you write (https://arnold-neumaier.at/ms/univQP.pdf page 29), "The situation is essentially the same for electrons and other particles. Their scattering produces spherical waves in which the electron field (and hence the charge) is delocalized and locally fractional. For...- Spinnor
- Post #38
- Forum: Quantum Interpretations and Foundations
-
High School Feynman QED Questions
I think the book is based on a series of lectures he gave, Your questions my be answered by watching them. The arrows in question spin very fast but also shrink in length proportional to the 1/(length of the path)? If the path length difference is of order the wavelength of the light the...- Spinnor
- Post #9
- Forum: Quantum Physics
-
Undergrad A short attenuated laser pulse, LIGO, and a fast detector
Edit, after some thought I want to remove the power recycling mirror from the interferometer below. I think that will simplify my thought experiment. Assume we have a LIGO type interferometer which is adjusted so that all light exits the detector port. Fire a single short attenuated laser pulse...- Spinnor
- Thread
- Replies: 1
- Forum: Quantum Physics
-
Undergrad Femto-photography Michelson Morley Interferometer thought experiment
That was part of the technical hurdles I suggested there might be. Preform the experiment in water or a small amount of smoke should do the trick?- Spinnor
- Post #3
- Forum: Quantum Physics
-
Undergrad Femto-photography Michelson Morley Interferometer thought experiment
Example of Femto-photography, I would like to know if I understand the results of a Femto-photography Michelson Morley interferometer thought experiment. From a Google search of Femto-photography, Femto-photography is a technique that visualizes the propagation of light at an incredibly high...- Spinnor
- Thread
- Replies: 2
- Forum: Quantum Physics
-
Suspect Samsung phone, hard to really "wipe" it clean?
It should be easy to 100 percent clean your phone, I will grant you a reset probably gets you pretty close and is simple. My current phone was bought used through a 3rd party, it might have yuk in it? Maybe just a matter of taking it as a challenge and get to it. Thank you.- Spinnor
- Post #5
- Forum: Computing and Technology
-
Suspect Samsung phone, hard to really "wipe" it clean?
The paranoid in my head says they will install their own malware. 😬- Spinnor
- Post #3
- Forum: Computing and Technology
-
Suspect Samsung phone, hard to really "wipe" it clean?
My wife got a nice new used phone from a friend for me. Being paranoid I don't trust the phone. Google tells me that a factory reset will not necessarily rid the phone of possible evil malware. Further Google tells me there is a process "flash a new image on my phone bootloader mode" that should...- Spinnor
- Thread
- Security
- Replies: 5
- Forum: Computing and Technology
-
Undergrad Feynman's summing arrows for photon amplitudes applied to LIGO?
I think most of his students that sat through the Feynman lectures on physics would agree with you, I think he points this out in the last lecture?- Spinnor
- Post #5
- Forum: Quantum Physics
-
Undergrad Feynman's summing arrows for photon amplitudes applied to LIGO?
I don't think it is, I think he represents this technique as basis of quantum electrodynamics but to be sure I would have to watch his Auckland lectures again.- Spinnor
- Post #3
- Forum: Quantum Physics