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Smartdot not so smart
Posted: Mon Jan 11, 2021 1:16 pm
by Beaker
Surprisingly a sticker on your phone doesn’t stop teh fivegeezzz! All the usual frequency aligning bs...
You can even get one to stick on your dog.
https://www.bbc.co.uk/news/technology-55613452
Re: Smartdot not so smart
Posted: Tue Jan 12, 2021 2:58 pm
by TimW
Do dogs give off EMF then? I didn't know that.
Re: Smartdot not so smart
Posted: Tue Jan 12, 2021 4:24 pm
by KAJ
TimW wrote: ↑Tue Jan 12, 2021 2:58 pm
Do dogs give off EMF then? I didn't know that.
Does anything (including a hole)
not give off EMF?
Re: Smartdot not so smart
Posted: Tue Jan 12, 2021 11:59 pm
by dyqik
KAJ wrote: ↑Tue Jan 12, 2021 4:24 pm
TimW wrote: ↑Tue Jan 12, 2021 2:58 pm
Do dogs give off EMF then? I didn't know that.
Does anything (including a hole)
not give off EMF?
No. Although only via Hawking radiation for an isolated black hole.
It's the third law of thermodynamics at work.
Re: Smartdot not so smart
Posted: Wed Jan 13, 2021 5:48 am
by monkey
dyqik wrote: ↑Tue Jan 12, 2021 11:59 pm
KAJ wrote: ↑Tue Jan 12, 2021 4:24 pm
TimW wrote: ↑Tue Jan 12, 2021 2:58 pm
Do dogs give off EMF then? I didn't know that.
Does anything (including a hole)
not give off EMF?
No. Although only via Hawking radiation for an isolated black hole.
It's the third law of thermodynamics at work.
Does an electron falling into a hole in an LED, or similar, and putting out a photon count?
Re: Smartdot not so smart
Posted: Wed Jan 13, 2021 12:46 pm
by dyqik
monkey wrote: ↑Wed Jan 13, 2021 5:48 am
dyqik wrote: ↑Tue Jan 12, 2021 11:59 pm
KAJ wrote: ↑Tue Jan 12, 2021 4:24 pm
Does anything (including a hole)
not give off EMF?
No. Although only via Hawking radiation for an isolated black hole.
It's the third law of thermodynamics at work.
Does an electron falling into a hole in an LED, or similar, and putting out a photon count?
Yes.
Re: Smartdot not so smart
Posted: Thu Jan 14, 2021 1:20 pm
by Little waster
TimW wrote: ↑Tue Jan 12, 2021 2:58 pm
Do dogs give off EMF then? I didn't know that.
Dogs tend to be coated in a cloud of negatively-charged ions.
Cat ions on the other hand are positive.
Re: Smartdot not so smart
Posted: Thu Jan 14, 2021 3:22 pm
by Gfamily
Little waster wrote: ↑Thu Jan 14, 2021 1:20 pm
TimW wrote: ↑Tue Jan 12, 2021 2:58 pm
Do dogs give off EMF then? I didn't know that.
Dogs tend to be coated in a cloud of negatively-charged ions.
Cat ions on the other hand are positive.
chateau!
Re: Smartdot not so smart
Posted: Thu Jan 14, 2021 6:08 pm
by dyqik
dyqik wrote: ↑Wed Jan 13, 2021 12:46 pm
monkey wrote: ↑Wed Jan 13, 2021 5:48 am
Does an electron falling into a hole in an LED, or similar, and putting out a photon count?
Yes.
Although I'd mildly dispute the idea that the carriers, particularly holes, in a semiconductor have any independent existence as a "thing".
Re: Smartdot not so smart
Posted: Thu Jan 14, 2021 6:35 pm
by monkey
dyqik wrote: ↑Thu Jan 14, 2021 6:08 pm
dyqik wrote: ↑Wed Jan 13, 2021 12:46 pm
monkey wrote: ↑Wed Jan 13, 2021 5:48 am
Does an electron falling into a hole in an LED, or similar, and putting out a photon count?
Yes.
Although I'd mildly dispute the idea that the carriers, particularly holes, in a semiconductor have any independent existence as a "thing".
I wasn't sure about that either, that's why I asked
They do act like they're thing though. I liked the idea that even things that aren't can emit.
Re: Smartdot not so smart
Posted: Thu Jan 14, 2021 6:49 pm
by shpalman
Both electrons and holes can be treated as freely moving things once you apply their non-thingness by modifying their mass and you know what their energies are relative to each other. By the time you've got that far, holes are as much a thing or not-thing as electrons. Learning about k.p theory was nice because the electromagnetic interaction between the different waves which fit into the periodicity of the crystal is what "causes" the different bands to have different effective masses, some of which are negative. (You need to already know that the bands exist, and what their energies are at some point in the band structure, but then the optical matrix elements between the bands does the rest.)
But then the mass, charge, and electromagnetic interaction strength of electrons and positrons are needed as input to the Standard Model.
Re: Smartdot not so smart
Posted: Thu Jan 14, 2021 7:18 pm
by dyqik
shpalman wrote: ↑Thu Jan 14, 2021 6:49 pm
Both electrons and holes can be treated as freely moving things once you apply their non-thingness by modifying their mass and you know what their energies are relative to each other. By the time you've got that far, holes are as much a thing or not-thing as electrons. Learning about k.p theory was nice because the electromagnetic interaction between the different waves which fit into the periodicity of the crystal is what "causes" the different bands to have different effective masses, some of which are negative. (You need to already know that the bands exist, and what their energies are at some point in the band structure, but then the optical matrix elements between the bands does the rest.)
But then the mass, charge, and electromagnetic interaction strength of electrons and positrons are needed as input to the Standard Model.
That last bit is why I wouldn't argue for the non-thinginess of carriers _too_ strongly.
Re: Smartdot not so smart
Posted: Tue Jan 19, 2021 10:33 am
by jimbob
shpalman wrote: ↑Thu Jan 14, 2021 6:49 pm
Both electrons and holes can be treated as freely moving things once you apply their non-thingness by modifying their mass and you know what their energies are relative to each other. By the time you've got that far, holes are as much a thing or not-thing as electrons. Learning about k.p theory was nice because the electromagnetic interaction between the different waves which fit into the periodicity of the crystal is what "causes" the different bands to have different effective masses, some of which are negative. (You need to already know that the bands exist, and what their energies are at some point in the band structure, but then the optical matrix elements between the bands does the rest.)
But then the mass, charge, and electromagnetic interaction strength of electrons and positrons are needed as input to the Standard Model.
I have a colleague who pretends to not believe in holes.
It makes for a moderately diverting lunchtime discussion
Re: Smartdot not so smart
Posted: Tue Jan 19, 2021 11:05 am
by Little waster
jimbob wrote: ↑Tue Jan 19, 2021 10:33 am
shpalman wrote: ↑Thu Jan 14, 2021 6:49 pm
Both electrons and holes can be treated as freely moving things once you apply their non-thingness by modifying their mass and you know what their energies are relative to each other. By the time you've got that far, holes are as much a thing or not-thing as electrons. Learning about k.p theory was nice because the electromagnetic interaction between the different waves which fit into the periodicity of the crystal is what "causes" the different bands to have different effective masses, some of which are negative. (You need to already know that the bands exist, and what their energies are at some point in the band structure, but then the optical matrix elements between the bands does the rest.)
But then the mass, charge, and electromagnetic interaction strength of electrons and positrons are needed as input to the Standard Model.
I have a colleague who pretends to not believe in holes.
It makes for a moderately diverting lunchtime discussion
Jimbob, just another shill for Big Hole.