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location Cologne, Germany
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visits member for 3 years, 2 months
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Functional programming enthusiast, audio engineer & musician. Whilst not busy with any of that, I study physics at Universität zu Köln / Bonn-Cologne Graduate School.


1d
answered Is the potential in Schrödinger equation an operator?
Jul
15
comment Trying to combine red, green and blue to produce white
Pity Jin's original proposal for a dark background on Physics.SE didn't make it!
Jul
14
comment How can molecule of a few angstroms absorb visible light of a few hundred nanometers?
Basically the same reason a microphone of a few millimetres can pick up bass frequencies of several meters wavelength.
Jul
13
revised Is the principle of Conservation of Energy empirically verifiable?
Hypothesis 2 should imply something as well.
Jul
9
comment Negative sound rooms
Regarding the craziness... that's largely nonsense except if you have claustrophobic tendencies. There's a nice Veritasium video on silent chambers.
Jul
3
comment Why is the second the SI base unit for time?
@garyp: I'd counter that. Surely the obvious number of fingers to equip His creatures with is 42, so obvious indeed that it would be a dead giveaway had He actually chosen it, thus conclusively proving Himself a puff of logic. Since we do not in fact have 42 fingers⁽ⁱᵗ⁴ᵗⁱ⁰ⁿ ⁿ³³⁹³⁹, God must therefore exist. ⬛
Jun
29
answered Why can't the work done by a non-conservative force be zero?
Jun
29
reviewed Approve suggested edit on Derivation of Landau diamagnetism
Jun
28
comment What does a wing do that an engine can't?
@Jonas: drag is made up of a frictional part and a part from diverting air momentum downwards. By making the wings very big and airflow slow, you can minimise both arbitrarily so it's indeed "possible" to stay airborne without engines... theoretically. In practise, big wings also come with big mass and sacrificing speed is only reasonable up to a certain point – when it becomes simpler to just build an airship.
Jun
20
comment Applying an operator to a function vs. a (ket) vector
"Like any vector, we can decompose..." well, yeah. Though it should be noted that all this holds on far less obvious grounds than physicists like to pretend. Vectors in general vector spaces, or general Hilbert spaces, may allow no basis expansion.
Jun
20
comment Based on note, how fast is a stringed instrument's string oscillating?
That'll have to be a visual representation with pretty crazy FPS count, so people could "see" the speed. The eye itself isn't fast enough. What you should be more concerned about is amplitude, then just blur the string over that range, implying that it vibrates faster-than-visible. That'll look far more convincing than an obviously-too-slow simulated vibration.
Jun
20
revised Applying an operator to a function vs. a (ket) vector
added 41 characters in body
Jun
19
answered Applying an operator to a function vs. a (ket) vector
Jun
7
comment Interference of independent electrons
That's quite correct. If you controlled the individual emission, you'd effectively separate the systems (in the time domain).
Jun
7
comment Interference of independent electrons
If the systems were seperate it would mean there's one laser shining at one target, and another shining at another target. Nothing interesting happens. If you want to observe interference, you need to have one connected system. Then, there are still individual photons – that's not the problem – but they can't be assigned to one or the other laser.
Jun
7
comment Interference of independent electrons
Again: interference happens no matter how low the incidence, because there is no such thing as individual photons from either source. garyp explained it rather better than I did. — Whether it produces an image or whatever else is not so relevant, it shows the interference, that's what matters. In any case the systems must not be seperate, otherwise each one behaves on its own and there cannot possibly be interference.
Jun
6
answered Interference of independent electrons
Jun
1
comment Why don't two musical instruments sometimes generate destructive interference?
@user6972: "almost all of the energy in fundamental" is profound nonsense except for some special cases (e.g. glockenspiel). In a lot of instruments, in lower registers the fundamental doesn't even have the strongest amplitude. Anyway, I don't think this is the right place for that discussion...
Jun
1
comment Why don't two musical instruments sometimes generate destructive interference?
@user6972: even if most of the energy is contained in the few lowest harmonics, Fletcher-Munson tends to shift the most audible part well into the higher harmonics (in particular for low tones – guitar and bass players normally use high flageolett notes for listening to the beat for tuning; those are also less overtone-rich). At any rate, in the beat you hear there is not proper destructive interference, see my other comment.
Jun
1
comment Why don't two musical instruments sometimes generate destructive interference?
@keshlam: most musicians do this when tuning by ear. It works by far best on two strings of a bowed instrument because the interference plays into the phase-locking loop. Even on a guitar, the beat is very audible when playing a detuned unison, but here it's mostly the change in the harmonics' relative amplitudes you hear (the ears being always better at "relative" than "absolute"). There's not normally at any time destructive interference as the OP asks for, i.e. such that the total loudness (RMS peak, whatever) is less than that of either of the single strings.