Talk:Two New Sciences

From Wikipedia, the free encyclopedia
Jump to: navigation, search


What is this page for? What is the formula for Galileo's ramp?

(William M. Connolley 20:35, 23 Mar 2005 (UTC)) That is a strange comment. Here is (I hope) a better one: the page says:

  • Galileo's experimental setup to measure the literal flow of time (see above), in order to describe the motion of a ball, was palpable enough and persuasive enough for Isaac Newton to state: I do not define time, space, place and motion, as being well known to all.
  • Even Einstein would state...

The quotes are accurate but I do not see anything to attribute Newtons or Einsteins statements back to Galileo.

The section is titled reactions by commentators. The fundamental nature of Galileo's experimental setup obviously affected the conception of time for the physicists who came after him: Newton, for sure, and even Einstein's conception of a clock in Special Relativity (but he went past this concept in GRT). Perhaps that needs to be stated, but that is a separate article that belongs to twentieth century physics. Ancheta Wis 01:17, 25 Mar 2005 (UTC)
The Time in physics article does not cite Galileo's conception of time, not even his discovery of the constant period of the pendulum. But his philosophical concept of time obviously influenced Newton's concept: "...time, of itself, and from its own nature flows equably without regard to anything external..."
There is a quine here. Galileo's conception of time was abstracted for part of the basis for Universal gravitation (meaning the use of derivatives with respect to time, and the integrals over time -- Newton's fluxions and fluents); but the flow of water under the influence of gravitation, as a water clock would cease to "flow equably" if water clocks A and B were to be accelerated or jerked. For example, close to Earth, on the International Space Station, the water clocks would cease to "flow equably".
In other words, Newton's gravitation was formulated using a conception of time which exploited gravitation. ("...time, of itself, and from its own nature...") The definitions seem to be resting on something which is self-referential, or an indirect self-reference.
Ancheta Wis 10:17, 25 Mar 2005 (UTC)
(William M. Connolley 11:33, 25 Mar 2005 (UTC)) The section is called reactions by commentators. But neither Newton or Einstein are commentators on Galileo. I don't think that section is appropriate.
Not trying for a disagreement here. The commentary is on Galileo's conception of time, not on the man or his attitude. It is not an accident that Stephen Hawking included them all in the same book. Ancheta Wis 11:51, 25 Mar 2005 (UTC)
If you are saying that the flow of time could be a separate article, I do not disagree. But it all rests on that water clock used by Galileo. Ancheta Wis 11:51, 25 Mar 2005 (UTC)
"So great a contribution to physics was Two New Sciences that scholars have long maintained that the book anticipated Isaac Newton's laws of motion." --Stephen Hawking, ed. p. 397, On the Shoulders of Giants. Ancheta Wis 12:13, 25 Mar 2005 (UTC)
"Galileo ... is the father of modern physics -- indeed of modern science" -- Albert Einstein. --Stephen Hawking, ed. p. 398, On the Shoulders of Giants. Ancheta Wis 12:18, 25 Mar 2005 (UTC)

(William M. Connolley 12:22, 25 Mar 2005 (UTC)) OK, I've read OTSOG too. But saying that Newton got his absolute time, as known to everyone, from Galileo, is over-interpreting. Its also a bit odd to attribute exactly the opposite - Einsteins rejection of absolute time - to the same source.

Now we're getting to one of my favorite topics, Newton's use of functions called fluxions and fluents. His use of the term mathematical time bespeaks that he obviously had a feeling for the flow of time. If you are saying that he didn't get it from Galileo, then where did he get it? Newton must have included Galileo as one of the Giants upon whose shoulders he was standing. Ancheta Wis 12:36, 25 Mar 2005 (UTC).

"What is this page for? What is the formula for Galileo's ramp?"[edit]

To answer the original question on the talk page, Galileo was able to "slow down" the rate of acceleration by inclining his wooden molding by some angle θ. Horizontal would be θ = 0 degrees, and vertical would be θ = 90 degrees. By taking ratios of the elapsed times and angles, he was able to determine that the acceleration of gravity was constant. But by rolling the hard bronze ball down the ramp at angle θ he was able to "slow down" the acceleration by a factor of sin(θ)

I see that the sine article uses radians; 90 degrees = π/2 radians.

Ancheta Wis 11:20, 25 Mar 2005 (UTC)

Stillman Drake[edit]

It should be noted that the initial contributor to this article, Wikipedian User:Dandrake is the son of this noted authority on Galileo. Note to Dan: WMC forced me to re-examine Newton's relationship to Galileo; hence the flow of time which I attribute to Galileo, and its provenance to Galileo is called into question. What I found from Westfall is that Galileo's Dialog was part of Newton's study (but no evidence of Discorso). Hence I was forced to find a new home for the flow of time text, which concept I still maintain originated from the Giant, Galileo. One uncomfortable note is that Stephen Hawking's reprint of the 5 Giants called it Dialog on Two New Sciences. Now I could have just used Hawking to parry the call, but it is probably just as well to have moved the Newton and Einstein reactions to the New Sciences to a new home. Ancheta Wis 16:34, 25 Mar 2005 (UTC) I should probably start filling in the red link to Stillman Drake. Would that be alright with you?

Galilean Transformations[edit]

Can some tell me if Galileo actually published his Galilean transformation in this book, or did he just explain the concept of relativity via the "cabin below decks in a sailing ship" example? What I am wondering is whether the Galilean transformations are a Newtonian interpretation of Galilean relativity, since I know Newton was big on absolute time. --Michael C. Price talk 20:59, 5 July 2006 (UTC)

It seems the sailing ship example comes from Galileo's 1632 Dialogue Concerning the Two Chief World Systems. It looks compatible with specicial relativity. Haven't tracked down the first appearance of the Galilean transformation yet. --Michael C. Price talk 06:01, 6 July 2006 (UTC)


The language in the infinite section looks anachronistic: It is therefore possible to have a one-to-one correspondence between the elements of a set N and the elements of a proper subset S of N. This cannot happen with finite sets. is sort-of attributed to Galileo. I bet he didn't say that William M. Connolley (talk) 07:03, 17 September 2011 (UTC)

For example, we cannot speak of infinite quantities as being the one greater or less than or equal to another [1] William M. Connolley (talk) 07:11, 17 September 2011 (UTC)

I've rewritten the first part. The second needs attention too William M. Connolley (talk) 10:32, 17 September 2011 (UTC)

Yeah, this section needs to be improved. How can it possible be said that Galileo's resolution is LESS powerful than the modern resolution? The modern resolution, "Oh its possible to have a bijection in subset S of N" seems meaningless and misses the significance of the concept itself of infinity -- I think it is even wrong to say that it has been resolved in a more satisfactory way. — Preceding unsigned comment added by (talk) 15:55, 4 September 2012 (UTC)

The modern resolution is more powerful because it allows you to compare finite and infinite numbers; Galileo's does not. It is hard to argue that infinite numbers are not "bigger" than finite ones; that Galileo doesn't even encompass this is a weakness. The modern resolution also allows you to compare different infinite numbers in a consistent way. Galileo cannot do this William M. Connolley (talk) 20:09, 30 December 2012 (UTC)

The 1914 edition states...[edit] (talk) 17:25, 30 December 2012 (UTC) The 1914 edition states: "Within twenty-five years after the death of Galileo, his Dialogues on Astronomy, and those on Two New Sciences, had been done into English by Thomas Salusbury and were worthily printed in two handsome quarto volumes. The Two New Sciences, which contains practically all that Galileo has to say on the subject of physics, issued from the English press in 1665. It is supposed that most of the copies were destroyed in the great London fire which occurred in the year following. We are not aware of any copy in America: even that belonging to the British Museum is an imperfect one.

Again in 1730 the Two New Sciences was done into English by Thomas Weston; but this book, now nearly two centuries old, is scarce and expensive. Moreover, the literalness with which this translation was made renders many passages either ambiguous or unintelligible to the modern reader. Other than these two, no English version has been made."

The last line of the second paragraph is therefore factually incorrect. It wasn't readily available in the USA until 1914, but there had been two English translations. [1]

WikiBlitz Oct 14, 2013[edit]

This article is going to be the subject of a WikiBlitz on October 14, 2013. My Fall 2013 History of Science survey. will be editing the article from 4:30-5:45pm CST. Kirwanfan (talk) 02:24, 14 October 2013 (UTC)