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John Cuthber

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Posts posted by John Cuthber

  1. In my opinion it's 42 this week but it will be a bit bigger next week, shrinking slowly after Easter; fortunately my opinion doesn't count for much.

     

    0* infinity =42

    Multiply both sides by zero (an odd opperation for a mathematician, but sort of legitimate. Division by zero is forbidden, not multiplication) and get

    0*0*infinity=0

     

    0*0=0 so I can simplify the first term and get

    0*infinity =0

    (zero squared really is zero; this simplification is legitimate)

     

    OK, that's one of the values you accept so we agree.

    This is an amusing game but contributes little to mathematics so those in charge simply banned it. Division by zero (and the equivalent multiplication by infinity) are not defined.

  2. I wrote "There is, at least potentially, another way to avoid that theoretical city's destruction. Stop acting in such a way as to make it easy for terrorist organisations to recruit followers. For example, do not detain people indefinitely without trial apparently on the basis that they are Muslims."

    And got the reply that

    "This is putting the cart before the horse. I empathize with the sentiment, but a better example could have been selected. It also fails to acknowledge the point that people are responsible for their own behavior. But as I said, I empathize with the sentiment. We can do much better on this front, and it appears that we really have no choice but to do so, since we can't keep going on like this."

     

    I haven't seen the proof, but according to one of this morning's newspapers the British man released earlier because they noticed that there was no evidence against him (the official reason for his detention was "possession of a suspicious device"; it was a battery charger) doesn't give any hope that the American Government has learned a lot about building bridges.

    Sure he was released as an innocent man against whom no charges had formally been made, and only 4 years late.

    The authorities saw fit to lead him out of jail in handcuffs and a blindfold.

    That's how they think one should treat the innocent (by their own admission) residents of a friendly country.

    If that turns out to be true then it's shameful. I think it's indefensible, does anyone disagree?

  3. It's very very nearly true, at any one time I doubt there's more than a few atoms of radioactive nitrogen in me formed by cosmic ray interactions. Of course some theories say that protons decay given time so there are no stable isotopes.

    I could use the ratio of the 2 stable nitrogen isotopes to look for patterns related to food etc in the same way that it can be done with carbon 13/ carbon 12 signatures. Why would they need to be radioactive?

     

    In fact, I couldn't do it with the radioisotopes of nitrogen because they are absurdly rare. Anyway since they don't last long enough to be digested there wouldn't be any point trying.

    I think you need to check some references.

  4. "And therefore to maintain our integrity amoungst the international community we must complete our goals."

    What were these goals?

    IIRC the major "goal" was to ensure that Saddam (who is now dead) didn't use his weapons of mass destruction (which never existed).

     

    The longer we stay there the easier it is for the likes of Bin Laden to say "look they are our enemies- they invade the countries of our brother Moslems".

    Only a tiny minority of Moslems are out to destroy the West, but the longer we stay in Iraq (and Afghanistan) the more difficult we make it for the moderates and the easier we make it for the radicals.

    Many of those in the international community think that this "war on terror" is just stiring things up.

  5. Bettina,

    Given that the UK has at the disposal of its armed forces everything up to and including nclear weapons I don't see how the statement "Diplomacy has to be backed up with strength which unfortunately puts the UK in a non bargaining position." makes sense.

    If you mean that we are weak because we try diplomacy first then I for one am quite happy to be weak.

  6. I didn't make that assumption. I was pointing out that Congress could declare war and clarify the matter. They have not. Presumably that's for a reason. Their reason may actually be valid. This might not really be a war.

    BTW, at camp Xray the American government doesn't seem to be struggling with the rules- it simply broke them.

     

    There is, at least potentially, another way to avoid that theoretical city's destruction. Stop acting in such a way as to make it easy for terrorist organisations to recruit followers. For example, do not detain people indefinitley without trial apparently on the basis that they are Moslems.

  7. I seem to recall an incident where a well organised military force tried to extract hostages from a situation. They knew where the hostages were, they had full plans of the building, they had plenty of time to plan their raid, they had vastly superior numbers and equipment, they had full access to the building and to the surrounding area.

     

    129 of the hostages died in the Moscow theater seige.

    I think diplomacy has its place.

  8. The whole thread is redundant because these things (like earwax) are not waste products.

    BTW, I strongly suspect that much of the liver's waste is excreted through the lungs.

  9. "When was the last time a war was officially declared?"

    Probably WWII but it hardly matters.

    The US constitution gives Congress the authority to declare war and they have not done so.

  10. "you can pass through it, just not out of it.

     

    isn`t that a little bit contradictory?"

    No, it just means it's a one way ticket.

    For a large (massive) enough black hole the event horizon is very large, so the gravitational field just outside it is nearly the same as just inside it. With only this small change in field strength there is nothing to pull you apart. It would be perfectly possible to go through the event horizon unscathed and without noticing.

    Later on, when you got nearer to the singularity, the gravitational field at your feet would be much bigger than that at your head and you'd be in trouble. The process is known coloquially as spaghettification.

  11. I don't know about you but all the nitrogen isotopes in me are stable. The lonest lived radioisotope has a half life of under 10 minutes. I think my tritium, thorium, radium, 90strontium etc, loading will contribute many orders of magnitude more radiation than any radioisotopes of nitrogen.

  12. The OED defines the ear as the organ of hearing.

    "Waste from the liver passes straight into the blood stream and out through the kidneys."

    Gosh! You don't say!. I thought it quantumn tunneled out.

  13. Glider,

    "I know of only one kind of sensory receptor cell that comes into direct contact with the external environment: the chemoreceptors lining the nasal cavity and on the tongue. All others are internal. Cochleal mechanoreceptorss are in the inner ear, photoreceptors are in the retina and all skin touch receptors are dermal or subdermal."

    True, but I was talking about organs rather than cells.

    Ears do stick out.

    Skin can shed waste products straight into the outside world in a way that, for example, a liver can't.

    Since earwax etc are not waste products anyway it hardly matters.

  14. I'm not sure I understand. Do you mean that for a field to act on the particle to accelerate it virtual photons have to reach the particle; catching up with the particle means they are red shifted an they have leass energy?

     

    If I have understood that bit then please help me ot here because my physics isn't that good.

    Imagine I have an electron between two metal plates. I put a voltage beween those plates and the electron accelerates towards the positive one.

    Do the virtual photons that carrry the energy move from the positive plate (in which case they would be blue shifted or the negative one (red shifted) and how do they know which plate to come from- after all, until they get there they don't know if I started with a positron?

    Do they come from both plates and, if so, do the effects cancel out?

  15. Looking at that curve I'd say it's clear that you have several acids present. What you need to do is work out which kink in the pH/ volume curve happens at the right pH to be carbonate rather than phosphate or citrate (or whatever)

  16. It may be a bit late to say this but did you measure the pH afterwards?

     

    I think the catalase solution you used was buffered (possibly by accident due to impurities) to some pH a bit lower than its optimum. When you added this to the dilute NaOH solution that was your pH10 solution you changed the pH to nearer the optimum and got a faster reaction. With the other solutions there was either not enough NaOH to get to the optimum or so much as to drive the pH further from the best value on the alkaline side. Adding acid wouldn't help if the stuff was too acid to begin with.

     

    What you need to do is repeat the experiment using buffer solutions to ensure that the pH stays (pretty nearly) the same when you mix the solutions.

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