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bio website ericmenze.com
location Minneapolis, MN
age 29
visits member for 1 year, 11 months
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I'm a Computer (Web) Programmer/Analyst based in Anchorage, AK and Minneapolis, MN. I use (among other things) ASP.NET, C# and SQL Server.

I build things. Bicycles, computers, websites, guitars, cars, motorcycles, sound sytems... lots of things.


Jun
25
comment To what extent are quantities fundamental?
"Which units are considered base units is a matter of choice. The base units of SI are actually not the smallest set possible. Smaller sets have been defined. For example, there are unit sets in which the electric and magnetic field have the same unit. This is based on physical laws that show that electric and magnetic field are actually different manifestations of the same phenomenon." - Wikipedia
Jun
25
comment To what extent are quantities fundamental?
Sure, but the SI unit choice was arbitrary to begin with. So you want 'the SI arbitrary choices, but different'? In the example I gave, I addressed this; we could make 'velocity' a fundamental base unit, which then along with whatever arbitrary 'time' unit we have, 'length' becomes a derived quantity. Or define velocity and length base units, and derive time. As in the quote above, some SI base units aren't fundamental at all (4/7 are really derived units; current is number of electrons per second, temperature up to a conversion factor).
Jun
25
comment Are there any other mechanisms that can make virtual particles 'real' other than Hawking Radiation and Universe Births?
I did include Krauss's proposed 'universe from nothing' as well, but really what I'm asking is; does the transition from 'virtual' particles to 'real' particles in a situation where there isn't an obvious energy source to rob like a black hole (also note that Hawking Radiation is a proposed mechanism, and may not exist). What I really want to get at is: if the particles DID become real, would they leave some sort of 'negative energy well' in the QED Foam where they formed? Could such a thing exist?
Jun
25
asked Are there any other mechanisms that can make virtual particles 'real' other than Hawking Radiation and Universe Births?
Jun
24
comment To what extent are quantities fundamental?
Not all 'systems' are equal. Imagine if the SI were defined pre-electrical discovery? There would be no coulomb or ampere in that system, varying the number of fundamental quantities. It could even change the quantities themselves, for example the meter is now defined off the speed of light, but the meter used to be a 'fundamental unit' before the speed of light was known (or even known to be constant).
Jun
24
comment To what extent are quantities fundamental?
Note that it doesn't specify "the smallest set", perhaps you mean 'base units' to be the "smallest complete set of fundamental units"?
Jun
24
comment To what extent are quantities fundamental?
To cut to the root of your question, I'm fairly certain that a given civilization or unit systems choice of what are 'fundamental units' are completely arbitrary. "A set of fundamental units is a set of units for physical quantities from which every other unit can be generated." (wikipedia)
Jun
24
comment To what extent are quantities fundamental?
Do you mean for the same system? One could postulate a civilization that is pre-relativity, and doesn't have $c$ defined. If you mean to also end up with the same result, I.E. express all of the SI system's units (and only those) then I think the answer is still yes. Could I not redefine length to use two 'arbitrary' new base units, like 'velocity of planet around main star(s)' and 'planetary rotation time'? What's your definition of 'base unit'?
Jun
24
comment To what extent are quantities fundamental?
That paper is great. Here's an illustrative quote from it: "The SI might be useful from the point of view of technology and metrology, but from the point of view of pure physics four out of its seven basic units are evidently derivative ones. Electric current is number of moving electrons per second. Temperature is up to a conversion factor"
Jun
24
answered To what extent are quantities fundamental?
May
28
awarded  Popular Question
May
14
awarded  Popular Question
Apr
23
awarded  Yearling
Jan
16
awarded  Tumbleweed
Jan
9
asked Is there an equation for the magnetic field of a conductor attached to a magnet?
Dec
19
comment Would it be possible to have an electron-less solid?
Is Metallic Hydrogen the only degenerate matter we've created, or is there anything else? en.wikipedia.org/wiki/Metallic_hydrogen
Dec
19
comment Would it be possible to have an electron-less solid?
So then, to finish the question off - would there ever be a temperature at which they would turn into a liquid or solid? Or conversely could they get all the way down to near absolute zero, and never be tempted (or be possible) to change their phase?
Dec
18
comment Would it be possible to have an electron-less solid?
Wow, point taken on the tennis ball sized matter calculation. Do we not have electric/magnetic fields that could hold together, say, a few hydrogen nuclei and repel any electrons from joining with them as they cooled? Or would any magnetic field be able to be that powerful / work in that manner?
Dec
18
comment Would it be possible to have an electron-less solid?
Hmm, a neutron star would be similar, but I was wondering if this was attainable on our planet or in our laboratories, which can't make quantum-degenerate matter as of yet (that I'm aware of). It's a good start though, thanks!
Dec
18
asked Would it be possible to have an electron-less solid?