for questions about design, process, data, or analysis of experiments and observations.

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4
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3answers
648 views

Have the Rowan University “hydrino” findings been replicated elsewhere?

In 2009, Rowan University released a paper claiming to replicate Blacklight Power's results on energy generation using hydrino states of the hydrogen atom. The paper (link now dead) appears to ...
77
votes
5answers
6k views

What was the major discovery on gravitational waves made March 17th, 2014, in the BICEP2 experiment?

The Harvard-Smithsonian Centre for Astrophysics held a press conference today to announce a major discovery relating to gravitational waves. What was their announcement, and what are the implications? ...
28
votes
6answers
10k views

Is this kids experiment a legitimate way to show that air has mass?

Consider the experiment in this link. The experiment includes using a ruler as a lever, with an inflated balloon on one side and a balloon which is not inflated on the other. The aim of the ...
10
votes
2answers
1k views

How are Monte Carlo simulations used in experimental high energy physics?

How are Monte Carlo simulations used in experimental high energy physics? Particularly in studying detectors limitations (efficiencies?) and data analysis. I will appreciate giving a simple example ...
16
votes
6answers
632 views

Has a double slit experiment ever been done using a track chamber or even contemplated?

I tried searches and the question has been posed in other fora, but no experiment came up. Track chambers (cloud chambers, bubble chambers , time projection chambers, solid state detectors like the ...
17
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5answers
6k views

Which experiments prove atomic theory?

Which experiments prove atomic theory? Sub-atomic theories: atoms have: nuclei; electrons; protons; and neutrons. That the number of electrons atoms have determines their relationship with other ...
21
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2answers
2k views

What exactly do we see on the famous neutrino image of the sun?

An answer to the question If we could build a neutrino telescope, what would we see? contains a link to a neutrino image of the sun by the Super-Kamiokande neutrino detector. There it says that ...
7
votes
3answers
21k views

Is the Earth negatively or positively charged?

The Earth carries a negative electric charge of roughly 500 thousand Coulombs. Does that mean the Earth is negatively charged?
7
votes
4answers
818 views

Experimental evidence for parallel universes/multiverses

My idea of physics is that it is a collection of mathematical laws relating observables. And that one can perform alot of mathematical derivations on these laws to produce new laws between ...
6
votes
2answers
830 views

Experiment which shows that Newtons third law is not true for magnetic forces

I am just reading David Morins "Introduction to Classical Mechanics". He writes about Newtons third law the following: It holds for forces of the “pushing” and “pulling” type, but it fails for ...
3
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4answers
4k views

How many digits of Pi are required in physics? [closed]

In other words: which physics experiment requires to know Pi with the highest precision?
2
votes
2answers
374 views

How the nucleon structure has been identified experimentally?

It is known that nucleons (proton, neutron) are composed of partons (quarks, etc.). How was this identified experimentally? In particular, how it has been identified that nucleons comprise of more ...
6
votes
5answers
3k views

What is the evidence for Inflation of the early universe?

The theory of Inflation explains the apparent consistency of the universe by proposing that the early universe grew exponentially for a 1E-36 seconds. Isn't a simpler explanation that the universe is ...
3
votes
1answer
259 views

Observable (in principle) signal of a bubble collision in eternal inflation

Assuming a scenario of eternal inflation with a lot of "bubble universes" expanding, Lenny Susskind explains here that a potential signal of a collision of our universe with another bubble could be a ...
2
votes
0answers
76 views

If two ends were a certain “length” apart were they therefore at rest (or at least rigid) to each other? [closed]

Considering the definition of the SI unit of "length" [1] and [2 (" method a.")] I'm missing any requirements about the two "ends" of the required "path travelled by light" being "at rest to each ...
6
votes
4answers
2k views

Measuring the speed of light and defining the metre - absolute or relative?

If the metre is now defined as the distance light travels in vacuum in 1⁄299,792,458th of a second and the speed of light is accepted to be ...
4
votes
5answers
856 views

Regarding string theory: how to refute the argument “if it cannot be tested experimentally then it is not science”? [duplicate]

Possible Duplicate: What differs string theory from philosophy or religion? I find a lot of people disbelieve in string theory, saying that since it cannot be tested experimentally then it ...
3
votes
2answers
880 views

Beryllium Vacuum Sphere Boat/Aircraft

Is it possible to make a solid rigid evacuated "balloon" out of Beryllium or other elements or alloys? The critical buckling pressure at which an evacuated sphere is given as $$ ...
2
votes
7answers
494 views

Can astronomers directly detect black holes?

Are there any methods of direct detection for black holes? I'm not referring to gravitational lensing, or measuring the orbits of a star in a binary pair. Is there any way of directly 'seeing' them? ...
0
votes
2answers
2k views

What were the intention/conclusions for Michelson-Morley experiment?

Which of the following were the intentions of M&M? to disprove the existence of aether. to show that the aether has no effect on matter and energy and therefore is as good as non-existent. ...
36
votes
4answers
2k views

What is needed to claim the discovery of the Higgs boson?

As I understand the Higg's boson can be discovered by the LHC because the collisions are done at an energy that is high enough to produce it and because the luminosity will be high enough also. But ...
28
votes
1answer
1k views

Status of experimental searches for tachyons?

Now that the dust has settled on the 2011 superluminal neutrino debacle at OPERA, I'm interested in understanding the current status of experimental searches for neutrinos. Although the OPERA claim ...
13
votes
1answer
1k views

How to determine the mass of a quark?

As far as I know quarks are never found in isolation, so how can we determine their rest mass?
34
votes
6answers
30k views

Why is jumping into water from high altitude fatal?

If I jump from an airplane straight positioned upright into the ocean, why is it the same as jumping straight on the ground? Water is a liquid as opposed to the ground, so I would expect that by ...
7
votes
5answers
986 views

Final theory in Physics: a mathematical existence proof?

Some time ago, I read something like this about the issue of "a final theory" in Physics: "Concerning the physical laws, we have several positions as scientists There are no fundamental physical ...
18
votes
4answers
1k views

Is there experimental evidence that massless particles such as photons attract massive objects?

For instance evidence that a highly energetic laser beam attracts objects nearby? In the framework of Einstein's general relativity all energy curves spacetime and hence exerts an attraction, but my ...
20
votes
5answers
817 views

What experiments, other than Hubble Expansion, support the Dark Energy theory?

Dark energy is introduced as a constant inside Einstein's equations. Its primary purpose, from what I understand, is to make Einstein's equations compatible with the accelerating expansion of the ...
5
votes
2answers
735 views

Is there a different behavior between proton and antiproton beams at the Tevatron?

This question has its origin to the reference on the Aegis experiment at CERN where they aim to produce super cooled antihydrogen and detect whether its reaction to gravity is negative. It set me ...
28
votes
2answers
356 views

experimental bounds on spacetime torsion

Did Gravity Probe B provide any bounds on Einstein-Cartan torsion? is a non-zero torsion value at odds with the results regarding frame-dragging and geodetic effects?
6
votes
3answers
7k views

Have we managed to make a perfect vacuum?

Have we managed to make a device without any atom inside it on earth? I was reading about vacuum here, and I found in the examples part here that even on the best man made vacuum devices, there are ...
5
votes
2answers
487 views

What does the LHC do afterwards?

Astronomical telescopes are now mega projects and cost $1Bn and although they are pitched to solve the current interest of the day they are general purpose machines and with upgrades and new ...
9
votes
5answers
6k views

What experimental proof has been found of Einstein's theory?

As a casual science reader, I've always found the implications of relativity (inconsistent clocks after near-light-speed travel and various space-time paradoxes) to be confusing and magical-sounding. ...
4
votes
3answers
2k views

Active gravitational mass of the electron

In PSE here electrons are added to a sphere and gravitational modifications are expected. My question is: Is there any experiment that show that a negatively charged object is source of a stronger ...
3
votes
3answers
614 views

Has $E=mc^2$ been experimentally verified for macroscopic objects with potential energy?

In relation to this question: What is potential energy truly?, I'm wondering if $E=mc^2$ has been experimentally verified to hold true for macroscopic objects with increased potential energy? I'm ...
3
votes
2answers
690 views

How is it possible to come to a conclusion that Universe is a result of the Big Bang while we aren't able to observe the entire Universe?

-I'm not a religious person so this is not a denial. I'm just trying to understand the most fundamental topic about Universe. -I know the Big Bang cosmological model is not a law but it's a theory. ...
2
votes
2answers
613 views

What experiment(s) have or can refute the existence of an electron-particle “system” over the separate existence of a neutron within itself?

This question actually came about from a discussion of another question posed here The neutron is known to be comprised of an electron and a proton, and there are observations that the neutron can be ...
4
votes
1answer
327 views

How was Be-8's Half-Life of 7E-17 Second Determined?

Radionuclides occur with half-lives in a vast range of over 37 magnitudes as listed in this site. In question 7584, Lubos Motl explained how Gyr half-lives were determined. This method doesn't appear ...
4
votes
1answer
547 views

Gravitational waves detection, any news? [duplicate]

Is the detection of gravitational waves a reality with nowadays technology? Are there recent news?
4
votes
1answer
121 views

Where can I get the most accurate measurements of parton distribution functions?

Where would I look to get the most accurate experimental values of parton distribution functions for the proton? I know these functions aren't measured directly, but I'd basically like to find a fit ...
3
votes
2answers
320 views

What is the highest accuracy of measuring time differences achievable today?

I was wondering if it would be possible to shorten the distance between detectors when measuring the speed of neutrinos to, say, 7m rather than the current ~700km? In this way the distance traveled ...
2
votes
0answers
1k views

How would you go about finding the natural frequencies (resonance frequency) [closed]

How would you go about finding the natural frequencies of solid materials like wood (e.g., teak, pine), stone (e.g., marble, granite) liquid, etc?
0
votes
1answer
1k views

measuring electromagnetic induction

There is a famous law which says that a potential difference is produced across a conductor when it is exposed to a varying MF. But, how do you measure it to prove? It is quite practical. ...
11
votes
8answers
1k views

What is the name of the principle saying it is meaningless to talk/ask questions that can not be measured/tested?

Watching quantum mechanics lectures and it was mentioned that it is pointless/meaningless to try to talk/question things that can not be tested/measured. Is this a principle? And if so what is it's ...
10
votes
1answer
2k views

Experimental signature of topological superconductor

I was wondering if someone can provides some clear experimental signatures of a topological superconductors ? I was thinking about that, because for topological insulator, one of the hallmarks is ...
15
votes
6answers
5k views

What is the world's biggest Schrodinger cat?

How big is it by a truly quantum measurement? I am thinking of comparing Science magazines "Breakthrough of the Year" (BYOT) with the Zeilinger buckyball. The BYOT is a piezoelectric mechanical ...
13
votes
4answers
905 views

Can we measure an electromagnetic field?

As far as I can check, the Aharonov-Bohm effect is not -- contrary to what is claimed in the historical paper -- a demonstration that the vector potential $A$ has an intrinsic existence in quantum ...
9
votes
1answer
1k views

How is it possible to store antimatter?

Antimatter is simply the opposite of regular matter and will destroy itself and any regular matter it contacts in a flash of raw energy, emitting radiation. Now somehow, scientists have been able to ...
11
votes
2answers
980 views

Use of Monte-Carlo simulation in High-energy Physics

I've been doing some research into the analysis used in particle physics when determining the significance of a finding (e.g. the recent Higgs candidate was announced as a boson in the 125-126 ...
10
votes
4answers
425 views

Can all quantum superpositions be realized experimentally?

When textbooks in QM give example of finite dimensional Hilbert spaces they give examples of photon polarizations or of 2-states systems and sometimes they mention how one can achieve superposition in ...
8
votes
1answer
114 views

Detailed form of light waves in vacuum and how to test it experimentally?

Consider a light wave in vacuum. Do the $\vec{B}$ and $\vec{E}$ fields have to be orthogonal to each other? Since you can add constants to a solution to Maxwell's equation it doesn't seem neccesary ...