3,248 reputation
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bio website thefurloff.com
location Maryland
age
visits member for 2 years, 3 months
seen Nov 17 at 11:12

Aug
18
comment EmDrive Cavity modes
As an example en.wikipedia.org/wiki/Nuclear_photonic_rocket
Aug
17
comment EmDrive Cavity modes
Despite all the controversy this has generated, the problem I think is that people are not look at the obvious, this system does require a power source to operate and therefore generates some "heat". Geometry certainly plays a role in how "heat" is distributed. I don't buy into the advertised theory of the thing, but if it shown it is generating thrust its not because of the physical theory that is claimed. The thing generates "heat" from a power source and is designed to mimic a nozzle. It is not reaction-less as people are concerned, the question is whether it is particularly efficient.
Mar
2
comment Change in Angular momentum of a spinning superball
Additional discussion can be found in this paper which discusses how the effects of colliding with the ground serve to shift the direction of spin
Feb
12
comment Ambiguity in number of basis vectors
The issues of incompleteness enter through the axiomization approach developed by Von Neumann, the formalism is absolutely consistent, but the interpretation is left open and depends upon physical observation. Von Neumann was very clear on this point. "Uncertainty" is purely rooted in as part of arbitrariness in the outcome of physical observation. So there is nothing inconsistent in the math, just how we interpret what the math tells us. thefurloff.com/2014/02/12/…
Feb
2
comment Relation between representations of boson operators?
You definitely need some props for your user name regardless...
Feb
1
comment Thermal equilibrium and kinetic energies
The ratio of relative change in internal energy to the entropy, e.g. $T=\frac{\partial U}{\partial S}$
Jan
12
comment Does the Relativity Principle of Special Relativity imply homogeneity and isotropy of all the reference frames?
@Muphrid isotropy of spacetime is not the isotropy used in GR discussions. Isotropy used in GR is that of the 3d hypersurface which is analogous to the constant time snapshot of the universe in newtonian approaches. This is well defined in all the texts of GR, including Gravitation referenced above.
Jan
12
comment Why do we calculate energy by integrate the Signal squared?
Basically we are showing that power and energy are proportional to a conserved current which is measure the flow of conserved quantity (charge) over time. Another way to conceptualize it is to think in terms of accounting. If I have a budget and I use a double entry accounting process, debits and credits should sum to zero. So money in this system is the conserved charge. It flows through different accounts over time. Some things I use my money for give me greater marginal utility, analogous to voltage, making Utility analogous to power.
Jan
12
comment Why do we calculate energy by integrate the Signal squared?
Voltage is potential, current is the flow of charge. Power is simply energy per unit time. Charges are generators of a continuous symmetry via Noether's theorem and exist whenever there is a conserved current, e.g. the derivatives of the current in any direction sum to zero. P=VI is a statement about the proportionality of current to power. Although voltage can take a constant value, it can also vary as a function independent of the current. cont below.
Jan
12
comment Can the vacuum be filled with virtual micro-black holes?
@Slereah If you are talking about virtual particles you are talking QFT.
Aug
27
comment What does it mean that the universe is “infinite”?
@DavidZ I would caveat your answer heavily on the FLRW model is a complete and accurate model for the universe. The vacuum is sufficiently unstable (as far as we can tell) as to warrant an arbitrary cutoff.
Mar
14
comment Why does an airplane need to climb during a takeoff even if it is in emergency situation?
@MartinBeckett always better to be 6ft above then 6ft under
Mar
13
comment Why does an airplane need to climb during a takeoff even if it is in emergency situation?
Altitude is life.
Mar
10
comment What do the modes of fermion fields look like?
@DavidZaslavsky thanks
Mar
9
comment I don't understand what we really mean by voltage drop
@oyvey I think this will help.
Mar
8
comment I don't understand what we really mean by voltage drop
It might help to look at the operation of a voltmeter. If you attempted to measure the voltage in a wire on two points at the same side of a resistor you would see no voltage indication. If you chose points on opposite sides of the resistor, would see a voltage difference. If you wanted to see the voltage in a wire relative to ground, you would put one probe on the wire and the other on a conductive point outside the circuit. As pointed out in several answers, the voltage is a measure of potential, nothing more.
Mar
8
comment Tangent bundles and $\mathbb{C}P^n$ and $\mathbb{C}^n$
@dmckee I honestly don't think its developed well enough to be a pure math question, I would probably rather delete than to see it be excoriated by some of the pure mathematicians. If you think it will migrate, I would like the opportunity to delete.
Mar
6
comment Tangent bundles and $\mathbb{C}P^n$ and $\mathbb{C}^n$
@Qmechanic I will clarify tomorrow. The thought is concerned with compactified spaces on a manifold. My articulation is still being improved. Tangent spaces have a definite constraint to the number of dimensions as they are directly tied to the underlying manifold. The alternate question that I am trying to understand is if tangent spaces are by definition non-compact, then why not assume spacetime is not a tangent space to some compactified manifold? There are math elements, but I am considering in context of a string theory.
Mar
4
comment Tangent bundles and $\mathbb{C}P^n$ and $\mathbb{C}^n$
@Qmechanic Nothing in particular, however, I wanted to group the coordinates appropriately and so I borrowed $\big|$ from the idea of superspace notation.
Mar
3
comment Tangent bundles and $\mathbb{C}P^n$ and $\mathbb{C}^n$
@ChrisGerig thanks for the input, I added a reference, and some additional questions, I will revisit this later for further modifications.