View Profile: Ivan Viehoff - Cosmoquest Forum

Yesterday, 12:16 PM

Ivan Viehoff replied to a thread He3 resources of Solar System in Space/Astronomy Questions and Answers

So there is, Kulcinkski et all estimate, about 500,000 tonnes of He3 in 20% of the moon's surface, down to a depth of "several" metres, call it 5m. ...

2 replies | 49 view(s)

2013-Jun-16, 10:01 PM

Ivan Viehoff replied to a thread Bit rate of human brain in Science and Technology

I don't think compressing the data by not showing what the eye temporarily isn't looking at would work, because I don't think there is a predictive...

27 replies | 327 view(s)

2013-Jun-14, 07:50 AM

Ivan Viehoff replied to a thread An interesing math question in Science and Technology

Thank you for taking the trouble for making precise what I was saying.

19 replies | 380 view(s)

2013-Jun-12, 10:32 AM

Ivan Viehoff replied to a thread dumb nuclear question in Science and Technology

It is also difficult to obtain a sufficient quantity of competent people with requisite thought qualities, incentive to carry out the work...

27 replies | 441 view(s)

2013-Jun-12, 10:16 AM

Ivan Viehoff replied to a thread How will Humans survive on Mars in Space/Astronomy Questions and Answers

You are quite right. But if we can't even splash through puddles convincingly, better recognise the deep sea diving as really very diffcult. Tests...

12 replies | 218 view(s)

2013-Jun-11, 01:12 PM

Ivan Viehoff replied to a thread How will Humans survive on Mars in Space/Astronomy Questions and Answers

It should become obvious now that the answer is "with very considerable difficulty". Huge amounts of energy are needed to transport and melt ice,...

12 replies | 218 view(s)

2013-Jun-10, 09:47 PM

Ivan Viehoff replied to a thread An interesing math question in Science and Technology

To take a most basic example of real world calculation, you want to solve y = a^x for x in terms of y and a real parameter a, using natural logs so...

19 replies | 380 view(s)

2013-Jun-10, 09:02 PM

Ivan Viehoff replied to a thread Walking from a Pole to the Equator in Science and Technology

Coriolis force is why hurricanes spin in the direction they do, not the reason they travel in the direction they do. They travel in the direction...

16 replies | 293 view(s)

2013-Jun-10, 08:59 PM

Ivan Viehoff replied to a thread An interesing math question in Science and Technology

There are some questions where the answer is so pointless it is better to modify the question to something with a sensible answer. In reality if...

19 replies | 380 view(s)

2013-Jun-10, 03:39 PM

Ivan Viehoff replied to a thread Are facts as good as reality? in Off-Topic Babbling

Mathematical and logical theorems are proved without facts, and could be described as inherently true without regard to any facts about the real...

115 replies | 1714 view(s)

2013-Jun-10, 03:25 PM

Ivan Viehoff replied to a thread Last to post wins: The return. in Fun-n-Games

Not a journey worth taking, as you discovered. Multiple roots and complex values are all very well for consenting adults with a handful of special...

2655 replies | 92343 view(s)

2013-Jun-10, 02:24 PM

Ivan Viehoff replied to a thread Quantum Computers and RSA Encryption in Off-Topic Babbling

I think the quantum computer recently in the news was one that exploits quantum tunnelling effects rather than Qubits. There seem to be useful...

3 replies | 94 view(s)

2013-Jun-10, 02:20 PM

Ivan Viehoff replied to a thread Tornado Chasing - safety, ethics and a proposal for regulation in Off-Topic Babbling

Safe rooms above ground appear to be an adequate solution, and much cheaper than either of those (especially in areas where underground is tricky). I...

78 replies | 882 view(s)

2013-Jun-10, 02:12 PM

Ivan Viehoff replied to a thread Walking from a Pole to the Equator in Science and Technology

Most hurricanes start going westwards and - if they survive long enough, not all do - then "recurve" eastwards when they get further north. This is...

16 replies | 293 view(s)

2013-Jun-10, 02:05 PM

Ivan Viehoff replied to a thread An interesing math question in Science and Technology

It isn't the only one. There are also issues with exponents that admit multiple solutions. And also when there are complex solultions. In general...

19 replies | 380 view(s)

2013-Jun-10, 10:30 AM

Ivan Viehoff replied to a thread 0.999... again in Off-Topic Babbling

There is a bit of an issue with that whole presentation is that it doesn't fully explain all the conditions necessary for the arguments he makes to...

61 replies | 1012 view(s)

2013-Jun-10, 10:25 AM

Ivan Viehoff replied to a thread bayes and the three doors problem. in Off-Topic Babbling

Again it still depends upon priors which you do not give us information on. If we have a pretty good idea that Monty would only do this when he...

25 replies | 363 view(s)

2013-Jun-07, 03:44 PM

Ivan Viehoff replied to a thread New roman numeral in Off-Topic Babbling

Actually people in the mediaeval period got to inventing new Roman numerals, and E was used for 250 at that time.

11 replies | 236 view(s)

2013-Jun-07, 03:38 PM

Ivan Viehoff replied to a thread bayes and the three doors problem. in Off-Topic Babbling

By chance I just found this moments before spotting this thread. It has the basic-level explanation of the Monty Hall problem in the first few...

25 replies | 363 view(s)

2013-Jun-07, 03:30 PM

Ivan Viehoff replied to a thread 0.999... again in Off-Topic Babbling

Fwiw, I see that this comes as #2 in the 12 most disputed facts in mathematics as listed here. ...

61 replies | 1012 view(s)

2013-Jun-07, 12:58 PM

Ivan Viehoff replied to a thread A weird case of mistaken identity. in Off-Topic Babbling

I was once in a guesthouse in a low-income country and was awoken two hours before dawn by repetitive chanting of some phrases, getting louder and...

9 replies | 177 view(s)

2013-Jun-07, 12:43 PM

Ivan Viehoff replied to a thread Tornado Chasing - safety, ethics and a proposal for regulation in Off-Topic Babbling

That seems quite correct to me. It seems to be far more economic to build inexpensively, provide safety of life arrangements such as "safe rooms",...

78 replies | 882 view(s)

2013-Jun-07, 07:43 AM

Ivan Viehoff replied to a thread Alternative to vaccines, idea. in Science and Technology

Indeed, but you don't need to inject all badgers. Injecting enough badgers would make a big difference. One of the accelerators of the problem is...

29 replies | 450 view(s)

2013-Jun-07, 07:38 AM

Ivan Viehoff replied to a thread Alternative to vaccines, idea. in Science and Technology

They already do that. But by the time they discover it has got the disease, there is a high risk it has passed it on, because it develops slowly. ...

29 replies | 450 view(s)

2013-Jun-06, 09:49 AM

Ivan Viehoff replied to a thread 0.999... again in Off-Topic Babbling

That is why I was careful to say "not of much applicability". I managed to get through a maths degree without studying hyperreal or surreal numbers...

61 replies | 1012 view(s)

2013-Jun-05, 08:57 AM

Ivan Viehoff replied to a thread Acid in Science and Technology

pH measures the concentration of hydrogen ions. In a traditional base like sodium hydroxide, hydroxide ions mop up the hydrogen ions in neutral...

24 replies | 499 view(s)

2013-Jun-05, 08:40 AM

Ivan Viehoff replied to a thread Worst Case Of Preconceptional Obversation Bias I've Ever Heard Of! in Science and Technology

If that's the worst case of preconceptional observational bias you've come across, you've clearly never encountered what often passes for medical...

16 replies | 405 view(s)