Gravity and light: The curious case of a mobile mass and a hidden light source

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Discussion Overview

The discussion centers around an experiment involving a mobile mass on a torsional pendulum that appears to be influenced by a hidden light source. Participants explore the implications of this phenomenon on gravitational forces and the nature of light, while seeking clarification on the experimental setup and its validity.

Discussion Character

  • Exploratory
  • Technical explanation
  • Debate/contested

Main Points Raised

  • One participant describes an experiment where a mobile mass moves toward a hidden light source and returns to its original position when the light is turned off, suggesting a potential revision of gravitational force concepts.
  • Another participant questions the validity of the cited paper and requests a proper scientific citation format, expressing skepticism about the journal's credibility.
  • Some participants propose that light has energy and could affect spacetime similarly to mass, potentially generating gravitational effects.
  • Concerns are raised about possible confounding factors, such as air movement or the experimenter's influence on the setup, which could affect the results.
  • Participants emphasize the need for detailed experimental descriptions and proper citations to validate claims made in the discussion.

Areas of Agreement / Disagreement

There is no consensus among participants. Some support the idea that light may influence gravitational effects, while others challenge the validity of the experiment and its interpretation, highlighting the need for further clarification and proper citation.

Contextual Notes

Participants note limitations in the experimental description, including the lack of proper citation and potential confounding factors that could affect the results, such as air drafts or the experimenter's movements.

louisrancourt
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hi
Can you explain why a mobile mass is pushed towards a hidden light and goes back to original position when light is turned off. The mobile mass is at the end of a torsional pendulum suspended by trifilar small copper wire and is completely enclosed in a box. No air movement perceived.
Louis
 
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louisrancourt said:
hi
Can you explain why a mobile mass is pushed towards a hidden light and goes back to original position when light is turned off. The mobile mass is at the end of a torsional pendulum suspended by trifilar small copper wire and is completely enclosed in a box. No air movement perceived.
Louis

This description is vague and confusing. Please provide proper, published citation where this experiment has been published, per the requirement of our PF Rules.

Zz.
 
hi
The paper :The effect of light on gravitational attraction ' was puiblished in Physics essays, december 2011. More experiment for 3 years led to the same conclusion. It really seems that there was a pushing force on the mass. Maybe its time to revise our notion of gravitational forces and their nature.
Louis
 
louisrancourt said:
hi
The paper :The effect of light on gravitational attraction ' was puiblished in Physics essays, december 2011. More experiment for 3 years led to the same conclusion. It really seems that there was a pushing force on the mass. Maybe its time to revise our notion of gravitational forces and their nature.
Louis

1. This is a dubious journal.

2. You obviously have no clue on how to provide a proper scientific citation. Please use Author, Journal name, volume number, page number, year.

3. Have you tried to do a citation index on the paper and see how many references were made to it and whether this has been verified and explained?

Zz.
 
Maybe he speaks about something like this

http://en.wikipedia.org/wiki/Optical_tweezers

But that is interesting too

http://www.technologyreview.com/news/414412/light-repels-light/

light_x220.jpg
 
Sorry, but what you cite sounds nothing like what the OP described. Those experiments do not require us to "... revise our notion of gravitational forces... " Please wait for the OP to clarify.

Zz.
 
hi
I realized there was not enough details to explain what happened in the experiment.
A 50 cm torsion pendulum supported in its middle point by 3 fine copper wire is placed in a cubicle. 100 g mass are placed at each end of the pendulum. A 500 g mass is brought close to one end of the pendulum and a point is reached where the gravitational attraction of the 500 g mass is balanced by the restoring force of the torsion wires. When that equilibrium point is reached, a 30 degrees laminar red laser beam is passed between the 2 masses, without touching them. The mobile mass slowly gets closer to the 500 g mass. When the light is cut off, the mobile mass returns to its equilibrium point. There was no measurable increase of temperature, no air movement and no static electric field detected.
The effect begins right away and stops when the light is cut off. When the laser beam was directed on the opposite side of the 100 g mass, it moved again towards the light beam.
What physical process can explain these facts?
Any help will be appreciated.
Louis
 
What's the problem? Light has energy and thus affects spacetime the same way mass does, generating gravity.
 
If you have 100g and 500 g masses and are watching them move, whatever you are looking at, it's not gravity.
 
  • #10
Until this experiment is performed in vacuum in free fall, how does one not eliminate any possible Bernoulli / Venturi effects - that the laser might be causing the air to flow... or that heating of the air is causing an "up draft" of the air in the gravitational field?

Or that the masses are responding to the change in position of the experimenter as he moves around the apparatus to switch the laser on and off...?
 
  • #11
Again, it doesn't matter if it's air drafts or not. The central premise - that this is a measurement of gravity - is simply wrong.
 
  • #12
louisrancourt said:
hi
I realized there was not enough details to explain what happened in the experiment.
A 50 cm torsion pendulum supported in its middle point by 3 fine copper wire is placed in a cubicle. 100 g mass are placed at each end of the pendulum. A 500 g mass is brought close to one end of the pendulum and a point is reached where the gravitational attraction of the 500 g mass is balanced by the restoring force of the torsion wires. When that equilibrium point is reached, a 30 degrees laminar red laser beam is passed between the 2 masses, without touching them. The mobile mass slowly gets closer to the 500 g mass. When the light is cut off, the mobile mass returns to its equilibrium point. There was no measurable increase of temperature, no air movement and no static electric field detected.
The effect begins right away and stops when the light is cut off. When the laser beam was directed on the opposite side of the 100 g mass, it moved again towards the light beam.
What physical process can explain these facts?
Any help will be appreciated.
Louis

You still have not provided the proper citation, and thus, all we have to go by is your interpretation of the experiment. Sorry, but that isn't enough.

I'm an experimentalist. The DETAILS of the experiment, of ANY experiment, are vital, based on my experience of not only performing such experiments, but also in refereeing any manuscript submitted for publication. Your description alone is not sufficient.

So unless you are able to provide the proper citation, then this topic does not meet the criteria for the source of discussion that we have outlined in the PF Rules that you had agreed to. It will result in this thread being closed.

Zz.
 

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