swansont

! Moderator Note This is ridiculous. Thread closed

And you can't slow the spin down. It's intrinsic and quantized. You're stuck with it. The best you can do is arrange things so all the parts add to zero.

IOW, if spacetime is flat, energy is conserved, but once you have to go to another frame of reference (because of curved spacetime), energy will not be conserved — it is not invariant between frames.

Solar sails also try and leverage the fact that reflection gets you about twice the momentum kick as absorption.

Yes, we have been able to reach speeds to make these measurements, since we don't rely on human perception or other poor instrumentation like that. We use e.g. atomic clocks, which are sensitive to nanosecond-level amounts of time dilation. That permits us to see relativistic effects for speeds attainable with planes, trains and automobiles.

When you divide by the area the earth presents to the sun, you get a pressure about 5 microNewtons per square meter.

What happens if you scale by area instead of population? Transportation, among other aspects of infrastructure, has an area dependence.

Even if it was a natural phenomenon, we still should be able to account for where the energy goes and why temperatures are increasing. You can't simply dismiss it as natural and be done with it. It's still a science problem, demanding a scientific answer. But "it's natural" lacks one.

It's a different question to ask if it can be quantized as opposed to must be quantized. The values it depends on, classically — heat and temperature — are not. But in terms of number of states available to it, the answer is yes.

! Moderator Note vuquta, stop hijacking threads with off-topic discussion

This thread isn't the place to do that. It's meant to be a list of things to consider when creating a new topic, and a discussion of those items.

Staff can do it. You can report the post (lower left corner of the post rectangle) and say it's a duplicate.

It's suspect for a number of reasons, not the least of which is that only one group has found the results — nobody else can replicate it. What's needed is a different group, using a different method, giving the same results. Here's a good critique http://scienceblogs.com/principles/2010/09/_httpksjtrackermitedu20100907e.php

$2.2 Trillion

The solids that are the closest to blackbodies (high emissivities) are metals, which have quasi-free electrons in the conduction band that can collide. Neutral gas atoms can temporarily have a dipole moment when interacting/scattering. Molecules can have a permanent dipole moment. AFAIK, a changing (rotating) dipole also generate EM radiation.

Nope. The clocks are synced at the origin, not at the position of the lightning strike.

The beam has a finite width. Any pair of rays within the beam have an opportunity to interfere, depending on the path length from their location in the slit to the screen.

But it's not 0% time and 100% space. Time dilates asymptotically to infinity, and length contracts asymptotically to zero, as v approaches c. At that limit, there is no length. But you can't get into that frame (mathematically) from an inertial one, and you can't get from the frame of one photon to another. How are we to understand what a photon reference frame would look like, based on our experience with inertial frames?

How is conservation of angular momentum a consequence of this (or any) cosmological theory?

The syntax for the quote attribution is quote name='Great Orator' Using the "reply" button adds a timestamp and generates link to the post, so that's better to use when quoting a post.

Not all of the light goes through the slit. But for all of the light that does, energy is conserved.

I don't see where "simultaneous" is mentioned in either of those statements. In both cases it is made clear that the event is being observed in system K. If two events are simultaneous in K, they cannot be assumed to be simultaneous in other frames. As I said, simultaneity is frame-dependent. There's nothing here that contradicts that. Edit: You appear to be using "simultaneous" to refer to a single event viewed in multiple frames. That's not simultaneity. You can arbitrarily set clocks in multiple frames to be synchronized to one event (Not multiple events, though (separated by time or space)) just as you can arbitrarily choose one point in every frame to be the origin.

Axiomatic method? Mass-energy is not axiomatic, it is a conclusion based, ultimately, on observation, and experimentally confirmed. Objections to established science belong in speculations.

My typo — it's 930. Looked like 980 when I read it.

Pulling some material on the infrastructure spending from the Bush tax Cuts thread The answer to this was yes — Stewart did indeed lampoon this http://www.thedailyshow.com/watch/tue-september-7-2010/indecision-2010---are-you-ready-for-some-midterms- ending with "didn't we do this already? Shouldn't we have like a 22nd-century infrastructure by this point where the bridges and tunnels just come and pick us up at our houses?" I decided to look into this further. The part where Jon Stewart goes for the laugh — $50 billion on top of a previous $27 billion (from the video — for highways and bridges, from the $48 billion total assigned to infrastructure) is a lot of money. But how does it really stack up against the problem? As it turns out, the American Society of Civil Engineers (ASCE) does a periodic assessment of the infrastructure in the US. As far as I know they are nonpartisan (though they might be biased toward overstating the problem, as they are the ones who would be working on the solution), but here is the pertinent information from the report card for 2009: Bridges "A $17 billion annual investment is needed to substantially improve current bridge conditions. Currently, only $10.5 billion is spent annually on the construction and maintenance of bridges" The good news? Bridges got the second-highest grade in the report: C (behind solid waste, at C+) Roads "Americans spend 4.2 billion hours a year stuck in traffic at a cost of $78.2 billion a year--$710 per motorist. Roadway conditions are a significant factor in about one-third of traffic fatalities. Poor road conditions cost U.S. motorists $67 billion a year in repairs and operating costs--$333 per motorist; 33% of America's major roads are in poor or mediocre condition and 36% of the nation's major urban highways are congested. 1 The current spending level of $70.3 billion for highway capital improvements 2 is well below the estimated $186 billion needed annually to substantially improve the nation's highways. 3" Estimated spending of $380.5 billion vs. an estimated need of $980 930 billion, over a period of 5 years, for bridges + roads, a $549.5 billion shortfall. For all infrastructure, the estimated 5-year spending need is $2.2 trillion, with actual planned spending (at that time) at less than $900 billion (i.e. a shortfall of over $1.3 trillion). So the satire of the Daily Show belies the fact that no, what we're spending isn't going to get us to a "22nd century infrastructure." The stimulus and proposed additional spending on infrastructure, totaling ~$100 billion, is less than 10% of what is needed to make up that shortfall. We've inherited a whole bunch of infrastructure, and have squandered our inheritance by not maintaining it properly in order to propagate the illusion that low taxes are sustainable. And the problem with this is that it's gone on long enough that we erroneously think of these relatively low taxes as an entitlement.