1
vote
0answers
17 views

Quantum GCD circuit: Clearing ancillae

I am currently trying to implement a circuit for computing the greatest common divisor in the Quantum Computing Language. In my work, I partially proceed from the paper Quantum Circuits for GCD ...
-1
votes
1answer
29 views

The question of the protein and the ribosome

It is well known that proteins are spit out by ribosomes by reading the DNA that goes in. Now ribosomes are made of proteins. Doesn´t this mean that the riobosome structure came before the production ...
1
vote
0answers
23 views

Relativity Mapmaking in spacetime

The problem as stated: I do not know how I am supposed to map this. The instructions don't make sense to me and the textbook is really un-helpful. This is the map that I have to draw this on. I ...
0
votes
0answers
9 views

Black hole starship: Would micro black-hole Hawking radiation emit anti-matter?

My understanding of Hawking radiation is that virtual particle pairs of matter and anti-matter are created from vacuum energy and one of those virtual particles may escape while the other enters the ...
0
votes
1answer
35 views

Light is/produces a electromagnetic wave, but is the opposite also true?

A similar question has been asked, and to some extent the answer is: you need an antenna with $L \approx 200nm$. But it's not entirely clear to me if this is completely hypothetical, as "Marek" also ...
0
votes
3answers
40 views

How do free electrons conduct heat in a metal?

In a metal, how do free electrons conduct heat? Does the specific heat of a metal should be then related to the electrons and not the atom of the metal?
0
votes
0answers
44 views

On the Pauli Principle

Consider a quantum mechanical system as shown-say a piece of metallic conductor in the shape of a long, thin bar.(Must it be a single crystal to be considered a "system"?). Now focus on two free ...
0
votes
1answer
17 views

Simple Harmonic Motion given velocity and acceleration

I am trying to understand how to relate velocity and acceleration of an object to it's amplitude, period, and frequency given only the following: An object of mass m=20kg moves with SHM along the ...
0
votes
0answers
14 views

finding work done by the buoyant force on a submerged object [on hold]

A flotation device is in the shape of a right cylinder, with a height of 0.500 m and a face area of 4.00 m2 on top and bottom, and its density is 0.320 times that of fresh water. It is initially held ...
1
vote
2answers
44 views

How is refractive index related to the density of a medium (for example, air)?

I have a question regarding refractive index dependency on the density of a dielectric, specifically air. Background Let us start from Newton's second law form of driven harmonic oscillators ...
1
vote
0answers
25 views

Does a set of eigenvalues in QM correspond to a random variable in statistics? [duplicate]

In quantum mechanics the possible outcomes of a measurement of a quantity corresponding to a linear hermitian operator $A$ are only the eigenvalues $a_i$ of $A$ (see e.g. ...
2
votes
0answers
27 views

Decoherence and interpretations

With quantum decoherence, are there still any "gaps" in our knowledge of quantum mechanics that hint (either in terms of the physics, philosophy, or otherwise) at the need for further interpretation? ...
1
vote
1answer
47 views

Which of the properties of particles are intrinsic properties and why?

For macroscopic objects it's clear that - once observed - the observed property does exist for a while, even if we are no longer observing it. That has to do with the complexity and stability of such ...
0
votes
1answer
16 views

Why is a series resistor needed in a simple thermistor experiment?

I have come across the following simple question, however I can't see any need for a fixed resistor in series. The only possible reason that I can think of is that the resistance of the thermistor ...
1
vote
0answers
18 views

What are these cycles in orbital eccentricity called?

I have created a simulator for planetary systems. When I run it with our own solar system and plot the eccentricity, aphelion and perihelion of the orbit of Earth i get these cycles. Do these ...
-5
votes
0answers
39 views

New time theory? [on hold]

Without having big pretentions, in these few pages I will try to describe my views concerning time, speed, movement and the interesting (to me) conclusions, to which I have come to. First, let us ...
0
votes
0answers
21 views

Calculate the Bohr radius of a muonic atom

I want to better understand this problem and how to calculate the Bohr radius. The equation I found in my book is $r_n=\frac{n^2 \hbar^2}{mkZe^2}=\frac{n^2a_0}{Z}$. However, I found a problem online ...
0
votes
1answer
36 views

Differential derivation based upon time and space confusion

I have been doing a lot of derivations recently involving heat transfer. I was attempting to derive heat accumulation in a differential element based upon inflow and outflow as well as thermodynamic ...
0
votes
2answers
37 views

How can I clarify the difference between free falling and Newton's law?

After I have viewed two experiments the first about Newton's law which involves a brick block and feather letting them fall one time in a vacuumed room they fall at the same time and another time in ...
0
votes
1answer
22 views

Methods to solve a vapor pressure equilibrium question with water on the moon?

"Imagine a tall column of water on the Moon, maintained at a temperature of 50°C and left to the open vacuum at the top. Up to what depth will the water continue to boil? The Moon's radius is 0.273 ...
0
votes
1answer
28 views

Orbital angular momentum eigenstates in the $|\mathbf{r}\rangle$ representation

Consider the orbital angular momentum operators $L^2$ and $L_z$. In the $|\mathbf{r}\rangle$ representation using spherical coordinates those operators actions are given by ...
-1
votes
0answers
15 views

P-N Junction - (Depletion Region) [duplicate]

Will i have simple q ,,, Why the electron in N Type don't go to the Formed Positive Ions ?
1
vote
1answer
42 views

How the sun can burn that long? [duplicate]

I suddenly became curious that why the sun doesn't burn out at once? What makes the sun burn gradually?
0
votes
0answers
18 views

Pure State Entanglement and Private Communication

My question is about the relation between two protocols of transmitting a quantum message through a Quantum channel using entanglement (entanglement Transmission or generation for this question) and ...
0
votes
0answers
28 views

How did I get these strange electric shocks?

While doing experiment on designing & fabricating temparature controller circuit using a thermistor, this strange thing happened.Me & my friend frequently experienced short pulses of electric ...
0
votes
0answers
10 views

How to restict air flow without reducing pressure

I have a large volume of lightly pressurized air say 10000 cubic feet at 1 psi above atmospheric pressure. I want to move it to another area through a duct which is 20 in by 20 in. Airflow will be ...
0
votes
0answers
15 views

One from Landau's Minimum (Macroscopic Electrodynamics)

A dielectric sphere with the electric and magnetic susceptibilities ε1 and µ1 is rotating with angular frequency ω in a constant electric field E~ in a medium, characterized by the parameters ε2 and ...
0
votes
3answers
31 views

What is the electric field exactly on the surface of a conducting sphere?

Within the sphere, the electric field is 0, but is the electric field still 0 exactly on the surface?
0
votes
1answer
41 views

If you play more than one music track at once on a computer, does the sound heard get louder?

Say you are using a computer and have multiple Youtube videos playing music (or any other video) at the same time, does the sound produced by the computer's speakers (or a pair of headphones) become ...
0
votes
0answers
29 views

Entanglement in laser beams

Recent experiments in entanglement of two laser beams using OPOs indicates higher level of entanglement. But laser beams are nothing more than group of photons. How are the photons inside the two ...
1
vote
0answers
8 views

Forward and backward work distributions in fluctuation theorem

Fluctuation theorems such as Jarzynski equality and Crooks theorem (Link), show that $\frac{P_f(W)}{P_b(-W)}=\,exp[\beta(W- \,\Delta F)]$ where $W$ is work done on the system during each ...
1
vote
1answer
16 views

Wavelength for imaging an ultracold atom?

I was reading Stamper-Kurn's article Experimental Methods in Ultracold Atomic Physics (link). In the imaging section (page 13), he mentions: Cold atoms are conventionally probed by optical ...
0
votes
0answers
19 views

Measurement without collapse

Does anybody have a reference for Cini's model of Quantum Measurement theory. I have a background of Quantum Mechanics (Ballentine level). Also I don't have access to Cini's paper.
1
vote
0answers
23 views

In kerr's black hole solution can the Bekenstein-Hawking entropy be descrete?

In kerr's solution we have: $S_{BH}=\frac{k_{\beta}c^{3}A}{4G\hbar}$ where A is the area of the horizon and equal to $A=8\pi G^2 m(m+\sqrt{m^2 - a^2})$ where $a=\frac{J}{mc}$ and J is the angular ...
1
vote
0answers
15 views

COP and input work in a refrigerator

Where can i find a COP and input work requierd in a standard modern refrigerator? I need a sample refrigerator, so that I can calculate the heat disposed to the surrounding and use that to design an ...
3
votes
1answer
31 views

Why does energy flow between a high voltage transmission line and linemen approaching it on a helicopter?

The video High power line workers shows linemen servicing a live high voltage transmission line. As the helicopter approaches the line, the lineman reaches out with a metallic wand that is ...
2
votes
0answers
20 views

How to control a dc motor? [on hold]

I am in 8th standard and I am doing a project on 3d printing pens. I want to know how to control a dc motor, so that when I press a button it should increase its speed gradually till it reaches its ...
1
vote
0answers
23 views

How would you calculate consecutive bounces on a trampoline to find how much energy is lost each time or what percentage is lost each time? [on hold]

How would you calculate consecutive bounces on a trampoline to find how much energy is lost each time or what percentage is lost each time?
-6
votes
1answer
54 views

Change of Earth's Rotation [on hold]

At the time of global warming, all the ice will melt, resulting the reduction in spinning of earth, Initially. But, if earth's surface temperature rises continuously for a long time, exactly this will ...
-3
votes
0answers
15 views

Calculating fields of two magnets

I want to use two NEODYMIUM IRON BORON permanent magnets to create a repulsion between them. In which one PM is attached to the robot (which has three wheels and its weight is 5KG) and the another PM ...
0
votes
1answer
15 views

a question on work and kinetic energy [on hold]

A bullet has a mass of 0.02kg and is moving with a speed of 10m/s. It can penetrate 10cm of a given target before coming to rest. If the same target is only 6cm thick, what will be the speed and ...
0
votes
0answers
14 views

How can I calculate the bipartition angle for photoelectrons produced by photoelectric effect?

I'm taking a course in radiation physics and I'm studying the photoelectric effect. In the notes that he gave us my professor states that half of the emitted electrons are emitted forward with an ...
1
vote
0answers
6 views

why are triplet excitons more tightly bound than singlet?

In organic light emitting diodes, the Jablonski diagrams always show he T1 states to be lower in energy to the S1 states. They are also declared to be more tightly bound as a result. I don't ...
4
votes
0answers
51 views

Uniqueness of solution in newtonian mechanics

Recently I came across the problem of Norton's dome. I thought of two questions, for which I found no answer. Does there exist a newtonian initial value problem, where the total force on each body ...
0
votes
0answers
25 views

meson decay in Yukawa theory

I want to calculate decay width $\Gamma_{i\rightarrow f}$ (under assumption that we don't measure the polarization of particles in final state) in a decay process $$\phi \rightarrow \psi \bar{\psi}$$ ...
1
vote
1answer
25 views

acceleration and time dilation

Is it true that a freely-falling body accelerates because, as time slows toward the center of the earth, each second is longer than the preceding one, giving the body further to travel? A simple yes ...
0
votes
0answers
10 views

Would superconducting mirrors in a superposition of spatial states make a difference related to the dynamical Casimir effect?

Related to the dynamical Casimir effect: https://www.technologyreview.com/s/424111/first-observation-of-the-dynamical-casimir-effect/ Related to superposition of macroscopic objects: ...
0
votes
0answers
19 views

inlet velocity calculation from mass flow rate

I am struggling for following calculation, Could somebody please help me with this Mass flow rate and inlet velocity at 300 K and 40 mbar are 4.246 gm/minute and 32.8 cm/sec respectively, if the ...
1
vote
0answers
17 views

To which extent is the treatment of nuclear multipole radiation by the means of a classical electromagnetic field valid?

In the treatment of nuclear multipole radiation, for example in the context of nuclear gamma decay, it is standard, at least at the elementary level, to formalize the electromagnetic radiation as a ...
0
votes
1answer
25 views

Is the relation c=νλ valid only for Electromagnetic waves?

What is the validity of the relation $c = \nu\lambda$? More specifically, is this equation valid only for Electromagnetic waves? I read this statement in a book, which says: de Broglie waves are ...

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