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Comment Why not Just Link Textbook Chapters? (Score 5, Insightful) 205

Rather than poorly written, mistake filled blog pages on basic physics why not just link chapters from a physics textbook? The content is the same, there would be fewer mistakes in the physics since books are reviewed and edited and the writing style is less annoying.

The blogger this time forgets to include the knowledge that the universe's expansion is accelerating. We learnt this about a decade ago so it's not exactly new. The problem is that as the rate of expansion increases the volume of the universe which you can travel to without exceeding the speed of light shrinks. Given enough time it will become smaller than atoms and then nuclei etc. until you get to the planck scale and then nobody knows what will happen since we need a working quantum model for space-time itself which does not yet exist.

Now whether heat death or the 'big rip' kills off intelligence first is probably not clear - and I'm not sure I would really believe anyone who claims to know given the unknowns. However since space-time itself has a limited lifespan then intelligence clearly has a limited lifespan too unless we eventually figure out a way to leave the universe. That might be a tricky problem but we do have a lot of time to try and figure out a solution

Comment Re:No interaction means you don't know (Score 1) 226

..but if there were some way to make sure the two "copies" do not interact with anything.

That's my entire point! If you assume that you can make a system where there is no interaction then there is absolutely no difference whatsoever for all concerned between position A or position B. Hence there is absolutely no way to know whether you are in position A or B until you interact so there is no magical "teleportation". It's the same as Schrodinger's cat: the cat is either alive or dead and you find out which when you open the box and there is no undetermined state as per the common misconception.

To get the EPR paradox you need an entangled state for two particles. What you have is a single, unknown state of one particle (or person). These are not the same.

Comment Too low: don't forget the power requirements! (Score 4, Insightful) 597

I can see AC to the doorstep a big efficient whole house power supply that has 12vdc and 48vdc rails that are distributed thorough the house and battery backed, and few 220v "appliance circuits" off the AC.

48V and 12V lines are far too low to be sage and/or sensible. Remember that the power used is equal to the voltage times the current and that the heating of the wire carrying the current goes as the square of that current. Typical house wiring is good for ~30A of current and supplies several plugs in a room typically. With a 12V circuit you limit the power of all the devices connected to this circuit to 360W vs. the 6.6kW you get now (or 3.3kW if you live in North America). Even with a 48V circuit you only get 1.44 kW.

The result is that either you need to rewire the entire house with massively thick, and therefore expensive, cables to carry the far higher currents or you need to use a higher voltage for transmission. Even the factor of two reduction between Europe and Canada/US is noticeable for some devices: electric heaters are far punier than their European counterparts, kettles take far longer to boil, and Electric lawnmowers are practically useless etc. If you drop the voltage by another factor of 2-10 below even Canada/US then almost all devices will be impacted.

Comment Skin effect: DC more deadly at same voltage (Score 2) 597

Because you can't electrocute people with DC?

Actually it is easier to electrocute someone with DC the reason it rarely, if ever, happens is because most DC sources are very low voltage and cannot drive enough current through a human body to be a problem. A high frequency, alternating current is actually relatively safe because of something called the skin effect where only the outer surface of the object conducts the current. For a human this confines the current to your skin and away from vital organs like your heart. It is the reason why Tesla himself could discharge lightning bolts from his fingers without being electrocuted. However you do have to be careful since where the spark leaves your body can get burnt due to the heat of the plasma created.

Comment Re:faster than light never violates Relativity (Score 1) 226

Relativity requres that nothing can move through space as fast as light (c).

Not correct - light moves through space as fast as light. Nothing can move faster.

nothing moving faster than light can slow down to c

Actually it is stronger than that - nothing moving faster than 'c' should exist because of causality. If something moving faster that 'c' exists then then some inertial frames it will be propagating backwards in time. We could then use whatever it is to communicate with the past and set up all sorts of nasty temporal paradoxes.

Comment No interaction means you don't know (Score 1) 226

but, for the intents and purposes of outside human observers, haven't you instantly blinked across light years?

If you entangle two states such that the position is the only thing different between the two states then there can be no interaction with either 'copy' which differentiates between the two possible positions. The instant that there is an interaction which determines which state you are in (position A or B) that is the position you are in. It is no more mysterious than putting some one at the centre of a (very large) box and have them move away from that centre at almost the speed of light in an unknown direction. The person in the box does not know which direction they are moving in because there is nothing surrounding them and the people outside do not know until they open the box.

Comment Can't un-invent them (Score 1) 69

You realise we came close to a full scale nuclear war at least three times during the cold war?

Yes - and if we could un-invent the things I'd be absolutely for that. However complete disarmament would not help with a cold war scenario like this since the tensions were so high that paranoia would set in an one side would worry that the other side was rebuilding its nuclear weapons in secret and so start their own re-armament program in secret.

This leads to a potentially even more dangerous situation than having two sides each with a known nuclear arsenal. If one side believes that they are the first to re-arm how much more likely are they to use the devices in a pre-emptive strike than they would if they new the other side could retaliate in kind? Probably the best situation we can hope for is a world where only a handful of nations possess the devices and where each of their arsenals is limited. This preserves the deterrent while minimizing the risk of accident, or even worse, theft. Fortunately this seems to be the situation we are in although it would be great if the nuclear nations to reduced their stockpiles of warheads further.

Comment ...and even more inaccurate than usual (Score 4, Interesting) 148

There are several mistakes in the article as well. Supersymmetry is not a consequence of String Theory. It was invented to explain the huge difference between the Higgs mass and the energy scale where gravity becomes important (the fine-tuning or hierarchy problem). It was only after its invention that String Theorists realized that they needed it to make their theories work. In fact it is entirely possible that Supersymmetry exists and String Theory does not whereas the reverse is far less likely so it is wrong to say that SUSY is a consequence of String Theory.

Similarly the use of String Theory to solve non-perturbative QCD is not some new, fundamental principle but is simply a result of applying the maths developed for String Theory to a different problem. Hence studying the quark-gluon plasma is, at best, a test of some of the maths developed for String Theory but really tells us nothing at all about the physics. For a simpler analogy if you demonstrate that calculus works this does not imply that Newton's Laws of Motion are correct even though calculus was co-invented by Newton so he could write down and apply his laws.

Comment Re:Science != Biomedical Research (Score 2) 444

I don't mean easier as in effort- just in the scientific sense of having hypothesis or theories that are provable experimentally.

...and again I would say that while the challenge is different there is no reason to assume that medicine has it any more challenging that other fields. In medicine the data is relatively easy to collect but very hard to analyze because of all the interwoven factors. In particle physics the data is exceedingly hard to collect because of the conditions required to produce it but probably easier to analyze.

Building detectors and accelerators requires just as much scientific input as analysis: it is not just a question of effort. New approaches and technologies have to be developed to meet ever increasing performance requirements.

Comment Re:Science != Biomedical Research (Score 1) 444

I disagree. The ATLAS detector took 3,000 physicists well over a decade to design, build and test and that's before we even consider the similar effort which went into the LHC accelerator and the other large, multipurpose experiment, CMS. The challenges in other fields are different to those biomedical science but that does not in any way mean that it is easier.

Every bit of important, interesting research, regardless of field, has difficult challenges to overcome because if it did not someone would already have done it. You cannot just throw up your hands, say it is hard and then lower your standards until it becomes easy because at that point it is questionable whether the research you are doing has any value at all and, in some cases, even brings into question whether it actually counts as scientific research.

Comment Re:Science != Biomedical Research (Score 1) 444

I don't know if your post is a very subtle slur against psychology or not

It was not intended to be a slur against any field. It was intended to correct the slur that the author made on science in general and refocus it back to the specific field which the article itself referred to and which is the only one about which the author seems to be in any position to judge.

Comment Re:Science != Biomedical Research (Score 2) 444

Research being hard is not an excuse. The difficulty and assumptions should be made clear and the analysis should take this into account. I'd agree that have a 3 sigma evidence and 5 sigma discovery threshold probably will not work in other fields where it is hard to quantify the statistics accurately. I'd also say that medical research has far more of a problem with the media sensationalizing their results.

We had some similar problems in particle physics with claims being made and then retracted which is what lead to the 3 sigma/5 sigma rule. So medical researchers need to come up with standards for the medical field that are appropriate along with guidelines on how to present results so that it is hard for the media to sensationalize them. This might be a hard challenge to meet but this is research. If you are doing it because you think it should be easy you are in the wrong field.

Comment Re:The faster than light neutrino claim was very s (Score 1) 444

If I remember correctly, the scientists were saying that they MEASURED faster than light neutrinos, and were soliciting community aid in figuring out what was going on.

Not quite. They claimed evidence of FTL neutrinos and then tried to hedge their bet by asking for external experts to come and investigate to confirm. In fact a good proportional of the collaboration refused to sign the paper which is a very sure sign that you are on incredibly dodgy ground: if you cannot convince the vast majority of your fellow collaborators that the result is right you are unlikely to convince others and it should be a very clear message that you need to do more checks and get more data.

Comment No guarantee on the Leader (Score 1) 121

That's moot. They vote for the party, which is a vote for the leader of the party.

There is no guarantee that the leader of the party will remain the same. In the past the prime minister has changed between elections e.g. Thatcher, Blair etc. In fact even during the election there is no guarantee that the party leader will actually be elected: it is theoretically possible for a party to win the election and then have to find a new leader because the one they had lost their local seat. This certainly happens with the smaller parties: UKIP's leader did not get elected in the recent election even though others of his party did.

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