What is Experiment: Definition and 1000 Discussions
An experiment is a procedure carried out to support or refute a hypothesis. Experiments provide insight into cause-and-effect by demonstrating what outcome occurs when a particular factor is manipulated. Experiments vary greatly in goal and scale, but always rely on repeatable procedure and logical analysis of the results. There also exists natural experimental studies.
A child may carry out basic experiments to understand how things fall to the ground, while teams of scientists may take years of systematic investigation to advance their understanding of a phenomenon. Experiments and other types of hands-on activities are very important to student learning in the science classroom. Experiments can raise test scores and help a student become more engaged and interested in the material they are learning, especially when used over time. Experiments can vary from personal and informal natural comparisons (e.g. tasting a range of chocolates to find a favorite), to highly controlled (e.g. tests requiring complex apparatus overseen by many scientists that hope to discover information about subatomic particles). Uses of experiments vary considerably between the natural and human sciences.
Experiments typically include controls, which are designed to minimize the effects of variables other than the single independent variable. This increases the reliability of the results, often through a comparison between control measurements and the other measurements. Scientific controls are a part of the scientific method. Ideally, all variables in an experiment are controlled (accounted for by the control measurements) and none are uncontrolled. In such an experiment, if all controls work as expected, it is possible to conclude that the experiment works as intended, and that results are due to the effect of the tested variables.
Hey! Does anyone have the large/full description of Maxwell's demon thought experiment? I've read it on Wikipedia, but I was wondering if someone knows a better source I can reach legally.
Thanks.
https://www.wired.com/story/this-random-video-game-powers-quantum-entanglement-experiments/
I don't understand the principle of this experiment. The gamers produced random numbers, and what was done with these numbers then? Was the value like <S> in CHSH inequalities computed, and was it...
Hi,
as I know the barometric formula is an exponential equation, but when I did the experiment with a barometer at different heights and inserted these results in Excel for curve fitting, it showed a weird thing, I think. So exponential equation did show that R^2=0.942 and the second-degree...
Hello everyone,
I am now doing experiment related to quantum erasure. After plotting the correlation measurement with and without blocking one of the polarization from the SPDC source (say, V polarization), I do not know how to work further on the gating time from the rate of the random...
Hi. I’ve seen a number of schematic diagrams for the Delayed Choice Quantum Eraser experiment. Some include a prism to make the two idler photon paths diverge.
However, the prism is shown refracting the ‘idler rays’ in a way which contravenes Snell’s law. E.g. see prism marked ‘PS’ (not the...
The Eddington Experiment famously confirmed GR by showing, as Einstein had predicted, a deflection of starlight by the Sun that was double the deflection expected by Newtonian gravity. I don't understand where Einstein's 2x number came from. I make the following assumptions:
1. That a ray of...
In short, the Elitzur–Vaidman bomb experiment consists of a Mach–Zehnder interferometer, where a bomb is placed in one of the paths (I used the wikipedia description https://en.wikipedia.org/wiki/Elitzur%E2%80%93Vaidman_bomb_tester, and Sabine Hossenfelder's video: )
The bomb can be live or a...
TL;DR Summary: Help needed with plotting heat maps, using data we gathered in an experiment.
Hello,
so I'm having problems with analysing data, which we gathered from an experiment we did in class. This is meant as a type of non-guided experiments class, where we are just given an initial...
I was reading about Compton scattering. I have a question I did not find an answer for it in the book (Concepts of Modern Physics-Sixth Edition-Arthur Beiser) or in the internet search. My question is:
Is the incident X-ray beam, with the original wavelength, detected at different scattering...
Hi there!
High school physics teacher hoping to pick the brains of people who know more than I do here.
I'm curious whether the rate of photon emission has any noticeable effect on the diffraction pattern generated by the double-slit experiment.
To be clear: I understand a diffraction pattern...
Electrons are shot thru two slits separated by a distance s at a screen a distance ##z_0## away. The wave function for the particles is proportional to ## e^{ik \sqrt{(x-s/2)^2+z_0^2}} +e^{ik \sqrt{(x+s/2)^2+z_0^2}}##
Taking the first one, we can manipulate the square root algebraically...
Modification specifications:
Variation 1.
Placement of horizontal polarizer after BSa.
Placement of vertical polarizer after BSb.
Variation 2.
Placement of horizontal polarizer after Ma.
Placement of vertical polarizer after Mb.
Question1:
Is it safe to assume, that this modification...
Is it possible to tell which slit some of the light went through when the slits aren’t parallel (green & red boxes in option 3)?
I used a Bahtinov mask to cover the aperture of my 600mm f/9 lens while observing the star Polaris. Various open slits were tested while others were covered with...
I was reading Feynman's lecture on the double-slit experiment, the attempts to determine which slit an electron passes through.
https://www.feynmanlectures.caltech.edu/III_01.html#Ch1-S6
And the key part is when Feynman says, "Then a terrible thing happens.", about the low optical resolutions...
In Young's double split experiment, a narrow beam of light of wavelength ##589nm## passes through two slits to form an interference pattern on a screen which is a perpendicular distance of ##D## metres away from the slits. The slit separation is ##0.2mm## and the second bright fringe is ##6mm##...
Below are the statements in the "David Griffiths, Introduction to Elementary Particles 2nd Edition, 147~148 p.":
Evidently, the long-lived neutral kaon is not a perfect eigenstate of CP after all, but contains a small admixture of K1. The coefficient epsilon is a measure of nature's departure...
How was it justified before conducting the MICHELSON–MORLEY experiment to assume that the sun was at rest with respect to the ether? Also, was the ether assumed to have the same velocity with respect to the Earth throughout space at one instant in time, or like wind, with different velocities at...
In Kaur, M., Singh, M. Quantum double-double-slit experiment with momentum entangled photons. Sci Rep 10, 11427 (2020). https://doi.org/10.1038/s41598-020-68181-1 and in C. K. Hong and T. G. Noh, "Two-photon double-slit interference experiment," J. Opt. Soc. Am. B 15, 1192-1197 (1998) it is...
Hello,
I'm currently doing a school essay on the Magnus Effect, but I'm having a problem regarding a contradiction between my measurements and calculations.
The experiment consists of letting go of rolled A4 paper cylinders on top of a ramp set on a table so that when the cylinder rolls down...
https://arstechnica.com/science/2022/09/einstein-wins-again-space-satellite-confirms-weak-equivalence-principle/
See also http://dx.doi.org/10.1103/PhysRevLett.129.121102 (limited access)
My name is Joe,
I'm 36 years old and currently between work. I live in The city of Erie, Pennsylvania.
My interests are in the phields of electricity, physics, chemistry, and all engineering principles related. As I am only a high school graduate with no formal training, my education is self...
I can't find the anwer on this anywhere, so I hope I may ask it here.
My question: In a standard double slit experiment, according to the Many Worlds Interpretation, does the photon create different worlds with different impact locations of the photon?
So, without measuring which way...
I would like to know the opinions on the paper that I saw about Michelson-Morley experiment.
Michelson-Morley experiment was done in 1887 and had an impact on the future direction of physics. It is taught in schools as an experiment that proves the non-existence of the aether and proves the...
Hello,
I have a little problem understanding Young's slit experiment with single photons :
I have understood for a long time that each photon impact on the screen corresponds to a photon sent by the source, and that, if we don't try to find out by which path the photon has passed, of course...
Hello! For the experiment I am working on we are using as the ion source an ablation target. We have a 1 inch coin of the material of interest (ytterbium currently) and we send laser pulses to it (we are using a 532 Nd:YAG laser). Can someone point me towards a paper (or tell me from their...
What is the cost of lab experiments? I do understand that it depends, but let's say it's the cost of experiments conducted in a western country involving 1) strong magnetic fields; 2) plasma.
Also, can one find price lists for such things online?
Thanks.
This is the Two-Balloon Experiment: https://en.wikipedia.org/wiki/Two-balloon_experiment#cite_note-MW78-1
The claim on Wikipedia which I am a little confused over is that when 2 balloons (at the 2 red points) are connected via a tube, the smaller balloon at a higher pressure would push air...
A bit of background: I've read Derive the probability of spin at arbitrary angle is cos( ) | Physics Forums post in this forum and went into a "thought rabbit hole". It didn't make any sense to me and I think I made a wrong assumption somewhere along the way. Instead of typing everything out, I...
in a discussion on the twin experiment, I read that an author (Darwin) proposed that the non-inertial traveler twin sees the transition between the redshifts and blueshifts at the very moment when he turns around, while the inertial twin sees this transition with a delay, which means that for...
Pearson Physics 12 states:
"When the light sources have the same intensity but different frequencies, they produce the same maximum current"
However, Phet Simulation Photoelectric Effect seems to show that photocurrent changes with light frequency (eg see below for different photocurrents at...
There is no laboratory in my school ,looking for best chemistry project ideas for the 12th class students at minimal cost and that can be prepared at home .
need suggestions on this,response would be appreciated
I know for sure PICO will be measuring polarization anisotropies with high fidelity. In addition, the PICO science paper shows that it will make full-sky Compton-y maps but the plots are mostly limited to l=1000. Will PICO be able to measure kSZ temperature anisotropy at l=3000?
So I've been thinking for a long time now about making a self-submersible boat out of a plastic bottle without electronics. It should resurface by itself after a few minutes. I was thinking that it might increase its volume. By slowly dropping weights down the bottle and opening flaps on the...
Consider a Double Slits experiment in which the light source is monochromatic and each slit very narrow. There will be many fringes visible on either side of the axis.
1) If the light source is pulsed with very short, randomly spaced, pulses it will produce spectrally broadened radiation and...
I'm hoping this is basic and obvious, but assume it's not to the general public.
Ignore quantum mechanics and diffraction and assume a gun that can fire photons that each hit the center of a remote target. Place one of these and a conventional gun that shoots bullets at 1000 m/sec inside of a...
[Mentor Note -- LaTeX edited for readability]
I was thinking about an experiment to demonstrate gravitomagnetic effect. I did my calculations using gravitomagnetic model. It is not as accurate as general relativity, but GR should give similar predictions. I do not know if it would be possible...
In the experiment, I know that the spacing between successive valleys gives the excitation energy to be somewhere around 4.9eV. However, when you look at the plot, you can see that the spacing from zero to the first peak is much longer than any other spacings between two successive peaks. I was...
Let's take a beam of spin 1/2 particles prepared in the state |up> in the Z direction, let's pass it through a Stern& Gerlach apparatus in the X direction to get two beams of spin |right> and spin |left>, and then redirect these two beams directly in another inverted S&G to reunite them in one...
This is a simple experiment that demonstrates how it is possible to draw conclusions similar to those of quantum physics, without having to "invade" the microscopic world.
A student is led into a windowless room, which has only a slit in the ceiling.
The light that passes through the slit is...
Hello
Fresnel discovered that the shadow of a small disc had a bright point in its center. Experiment that he carried out by letting sunlight pass through a small hole (quasi-point source).
If, instead of looking at the shadow of the disk, we look (*) in the direction of the light source...
Hello
Sorry for my English...
We approach slowly (in a quasi-reversible way) an electrical charge of a glass of salt water.
Some ions arrange themselves in the glass.
What can we say about entropy of this transformation?
Bernadette
PS: My reflection comes from reading an old physics book...
Let us suppose I have a value measured from experiment and given by
$$V_{\text{exp}} \pm \sigma_{V_{\text{exp}}}$$ and a theoretical value given as
$$V_{\text{the}} \pm \sigma_{V_{\text{the}}}$$
Is there a statistical way to measure how well ##V_{\text{the}}## matches with the...
The changing magnetic field of a falling magnet induces currents in the pipe that slows it's fall through the pipe.
Question:
If the induced currents are decreasing the magnets descent then they must themselves have momentum. How is it dissipated once the magnet has passed through the end of...
I assume most people when they refer to Quantum Theory, they sort of referring to QFT.
So my question boils down to, what sort of an experiment could potentially refute QFTs (its plural because there are QF theories)?
I know that if we bring a positively charged rod closer to the electroscope, charges of electroscope are separated and the leaves of the electroscope get away from each other. but what happens if we touch the positively charged rod with our hands and then move the hand and rod away?
In the double-slit experiment with two open slits, is there a fixed relationship between the momentum (p) of the particle immediately after passing through the slit and the position (q) of the impact on the screen?
Hi Pfs
I read in the GHZ experiment article
that classical physics give an inéquality (a Bell like inequality)
Is there also sets of directions where this inequality is maximally violated ?
thanks
One of the reasons to suggest that light might be bent by gravity is the assumption that light is behaving as the other objects that bend their trajectories by gravity. On a similar ground, we could suggest that as the objects are experiencing Gravity Assist, then the light could be also...