Is History a Science?

This is how Newton understood motion (basically motion is a compound/conjugation/product of mass and speed - it's not a variation of position in time, that is the speed, the velocity - to use a closer word to Newton's) . You're playing with m*a = m*dv/dt = dp/dt with no respect to Newton's formulations.

And actually the formula ds/dt = kF is simply wrong because it doesn't fit the physical units in left (m/s) and right (N) terms. 

 

Let's cut off this ridiculous quarrel and let people talk about history if there's anything left to say.

 

Originally posted by Chilbudios Quantitas motus est mensura ejusdem orta ex velocitate et quantitate materiae conjunctim. This is how Newton understood motion (basically motion is a compound/conjugation/product of mass and speed - it's not a variation of position in time, that is the speed, the velocity - to use a closer word to Newton's) . You're playing with m*a = m*dv/dt = dp/dt with no respect to Newton's formulations.

Fine. But the point is that Newton considered the 'quantitate materiae' - 'mass' as we might say - to be independent of the speed. 'Motus' is therefore a constant times the velocity, and since it is constant, then d(mv)/dt = mdv/dt - the constant can be taken out of the brackets.

 

It's not until SR and the dependency of mass on speed that the (mv) can't be split up, and you need to substitute dp/dt.

 

And actually the formula ds/dt = kF is simply wrong because it doesn't fit the physical units in left (m/s) and right (N) terms.

You're ignoring the dimensionality of k. More importantly it is what Newton actually wrote. He said the 'change in the motion' was proportional to the force applied. Temporarily ignoring the question of what 'motion' means here - call it x - you therefore have directly dx/dt = k F - the change in something is a constant times the force. It is not necessarily a dimensionless constant, any more than g is a dimensionless constant.

 

If x is taken to be velocity (not speed) then the dimensions of k are 1/m in standard terminology, which balances the dimensional equation. 

Let's cut off this ridiculous quarrel and let people talk about history if there's anything left to say.

Edited by gcle2003 - 16-Sep-2006 at 08:39

It's not until SR and the dependency of mass on speed that the (mv) can't be split up, and you need to substitute dp/dt.

As I've shown motus for Newton means p, then Newton's own formula gives dp/dt, so no substitution is needed

 

You're ignoring the dimensionality of k. More importantly it is what Newton actually wrote. He said the 'change in the motion' was proportional to the force applied. Temporarily ignoring the question of what 'motion' means here - call it x - you therefore have directly dx/dt = k F - the change in something is a constant times the force. It is not necessarily a dimensionless constant, any more than g is a dimensionless constant.

If you bring original entities, please bring their definitions too. Usually, k is a numeric a-dimensional constant if not specified otherwise.
And you cannot claim your formula is implied by Newton's text because it's not. It was en euphemism to call it just wrong, but your insistence bring the revelation. F = m*dv/dt = m*d2s/dt2 - to write the force as function of space/position (s) and time (t) you have to invoke the double derivative!! (in plain English that would be the variation of the variation). Therefore, to use your original notation k = 1/m, the equations would look like d2s/dt2 = kF, not ds/dt = kF - a formula which has absolutely no connection to Newton's laws.

 

On the other hand, to a certain degree, we are abit more liberal to other views, because this is the scientific method! Simply coming up with one theory and dismissing anyone who things differently is not!

Science is making a theory and putting it to the test to see if it holds. In history, this means making an interpretation and seeing if others are possible. If all other views are considered 'anti-history', all progress is stopped, and history is dead.