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.

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  1. N

    Particle Maxwell's demon full experiment description

    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.
  2. S

    I Experiment with gamers, random numbers and entanglement

    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...
  3. N

    Weird barometric formula experiment results in Excel

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  4. physicsclaus

    How to calculate gating time from the rate of the random coincidence?

    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...
  5. S

    I Query on use of prism in delayed choice quantum eraser experiment

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  6. K

    B Eddington Exp vs Newton: Comparing Starlight Deflection

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  7. R

    B Does the bomb experiment do a measurement?

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  8. Rezex124

    Experiment - how temperature changes along a tube, using heaters

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  9. Viona

    I Compton scattering experiment

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  10. G

    Kinematics in Two Dimensions (Monkey and Hunter Thought Experiment)

  11. Mr Fallspring

    I Double-Slit Experiment: Does rate of photon emission matter?

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  12. J

    I Double Slit Experiment Mathematics

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  13. G

    A The experiment of Kim et al. (1999) (with small modification)

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  14. D

    B Non-parallel double slit experiment

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  15. T

    I Double-slit experiment, determining which slit an electron passed thru

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  16. A

    Second bright fringe in Young's Experiment

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  17. Y Y Kim

    I What is the meaning of 'CP violation' in the Cronin and Fitch experiment?

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  18. Ahmed1029

    I Michelson–Morley experiment and the velocity of the ether wind

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  19. Christian Thom

    I Double-slit experiment with momentum entangled pair of photons

    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...
  20. D

    I Magnus Effect experiment problem

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  21. Filip Larsen

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  22. J

    What are Joe's interests and goals as a new member and citizen scientist?

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  23. entropy1

    I Does the photon in a double slit experiment create many worlds?

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  24. V

    I Michelson-Morley: Errors in Calculations?

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  25. Marilyn67

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  26. Cody Livengood

    B Is there an experiment that shows strong force grows with distance?

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  27. K

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  28. A

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  29. P

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  30. N

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  31. Kairos

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  32. P

    I What were the real results of the photoelectric effect experiment?

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  33. Saba_467

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  34. SherLOCKed

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  35. M

    Construction How do you build a self-submersible boat?

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  36. G

    A A double slit thought experiment leading to a paradox

    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...
  37. P

    B Does this thought experiment show that Space must be curved?

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  38. olgerm

    I Gravitomagnetic Experiment: Possibility & Calculations

    [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...
  39. Terrycho

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  40. Christian Thom

    A Another thought experiment about spin 1/2

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  41. dom_quixote

    I Uncertainty in an experiment with an image viewed through a big slit

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  42. Bernadette

    B A variation on the Fresnel Spot experiment

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  43. Bernadette

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  44. Arman777

    A How to express the agreement between experiment and theoretical observations?

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  45. S

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  46. MathematicalPhysicist

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  47. MatinSAR

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  48. A

    A Double-Slit Experiment: Momentum & Position

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  49. H

    A What is the Bell-like Inequality in Classical Physics?

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  50. D

    B Proposed Experiment - Speed of Light

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