这个试验有很多争议,我学习时有过类似下面的想法。


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送交者: 短江学者 于 2007-10-21, 20:10:07:

回答: 请指教:关于伽利略的小球下落的理想试验,我觉得还是需要超常的智慧的 由 apple 于 2007-10-21, 19:34:56:

Galileo’s Thought Experiment Rethought

David Atkinson & Jeanne Peijnenburg (University of Groningen)

We argue that thought experiments should be looked upon with a critical, if not a distrustful eye.
Even the most famous thought experiment in history, viz. the argument by which Galileo claims
to refute Aristotle’s theory of falling bodies, does not attain the impeccable standard that is
generally assumed. Impressive as this thought experiment may be, it is in fact flawed, both in its
attempted refutation of the old, as in its attempted demonstration of the new ideas about falling
bodies. It is irrelevant here that Galileo lacked the knowledge that we possess; the point is that
situations can be envisaged in which Galileo’s claims are, and other situations in which they are
not correct.
We consider four ways in which two bodies fall the same distance:
1. in vacuo in a uniform gravitational field;
2. slowly in viscous fluids;
3. in the inhomogeneous field of the earth;
4. rapidly in viscous fluids.
In case 1, Galileo is right in claiming that the times of fall for both bodies are the same. In case
2, Aristotle is right in claiming that the times are inversely proportional to the weights. In case
3, Galileo’s thought experiment applies point by point, but his grand conclusion that the times
of fall are equal does not follow, nor is it generally true. In case 4, neither Galileo’s nor
Aristotle’s claims are true.
Our purpose in this talk is not to reinstate Aristotelian physics at the expense of Galileo, but
rather to show that even such an awe-inspiring thought experiment as that of Galileo is not as
decisive as it might seem, and that we need real experiments to teach us how bodies fall in
various situations.

Reference

David Atkinson and Jeanne Peijnenburg, Galileo and Prior Philosophy, Studies In History and
Philosophy of Science (Part A) 35, 2004, 115-136




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