Date: Thu, 12 May 2005 21:31:45 -0400 (EDT) From: "Keith F. Lynch" <kfl at KeithLynch.net> Subject: [WSFA] Re: Newton or einstein? To: WSFA members <WSFAlist at WSFA.org> Reply-To: WSFA members <WSFAlist at WSFA.org> Ern <elilley at mindspring.com> wrote: > Driving down the road (pe=1/2mv^2) I think you mean ke, not pe. > I was thinking about how we live in a newtonian world, and that > quantum physics is really besides the point. > Of course, I was listening to a cd at the time. > So, what do you think? Is Einstien irrelant in everday life? Einstein is mostly associated with relativity, not with quantum physics. Newtonian physics is a good approximation to reality for most purposes. But quantum works better if you're dealing with very small objects, small spaces, low energies, short durations, etc. And relativity works better if you're dealing with very high speeds, very strong gravity, or with vast amounts of time or space. (Unfortunately, general relativity and quantum physics aren't really compatible. But there's no way to figure out how they interact until we can work with an extremely strong but at the same time extremely tiny gravitational field.) As for CDs, one doesn't need to know anything about quantum physics, relativity, or even Newtonian physics to operate a CD player. Or even to repair one or to build one from components. In principle, CD players and everything else we have could have been invented with no knowledge of physics, though it would have taken much longer, with lots of wasted time, effort, materials, energy, and money. Biology also depends totally on quantum physics, but wasn't designed by anyone who knew anything about it (except in Kansas). It's worth learning relativity and quantum physics, not just for practical purposes, but because it's good to understand something about the world we live in. Living life without learning physics and math is like going on vacation to an exotic city filled with wonders, but never leaving your hotel room. > Do we live in a locally deterministic universe? Quantum physics would seem to imply not. What's weird about it isn't just that absolutely identical starting conditions can lead to differing ending conditions, or even that there are facts about reality that we can never know, but that those facts about reality aren't even "known" by the particles involved. It's not just that we don't know which of two possible paths an electron or a photon took -- it's that the electron or photon itself acts in a way that implies that it somehow took all possible paths. To me, this is much weirder than special relativity's lesson that space and time are interconvertable (i.e. some of what is space to you is time to me, and vice versa), or general relativity's lesson that space is curved (e.g. that the earth isn't quite 360 degrees around, but is "missing" about an inch). > Sent via BlackBerry from Cingular Wireless Is this tagline something you deliberately add? If it's automatically appended to your messages without your consent, I'd be glad to automatically remove it, as I do the various Yahoo! taglines.