Most interesting was the way they did obtain the image: series of pixels from synchronised telescopes, and then processing the combined information. Pixels taken from different places on earth virtually turning earth into giant dish. In essence an extension of diurnal parallax idea to measure distance to the moon. We discussed diurnal & annual parallax in this thread above.
I wonder if any of the more scientifically minded people on here could help me, please.
- Thread starter Horsa
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Most interesting was the way they did obtain the image: series of pixels from synchronised telescopes, and then processing the combined information. Pixels taken from different places on earth virtually turning earth into giant dish. In essence an extension of diurnal parallax idea to measure distance to the moon. We discussed diurnal & annual parallax in this thread above.
I watched a programme earlier this week & found it disturbing that whitening toothpastes & whitening treatments contain hydrogen peroxide or hair bleach. Luckily, I don't use them. Does anyone else find this hard to swallow? Hair bleach getting inside people. Think of all the damage that could do.
People prefer to look pretty/fashionable at the expense of health. And dark teeth are real problem for them. Especially if they have couple implants that look freshly white & shiny while real teeth in between are dark yellow and ugly. Not everyone is like Shane MacGowan who does accept how he looks and does not want to change it (a different issue is that substance abuse contributed badly to Shane's look)most people prefer to look better and feel much better as a result. A compromise between the mental & physical health in this case. Similar, even most pathetic case is breast enlargement/silicone implants in women. Why do healthy women ever do that? It does not make sense. Yet they do, such powerful is the desire and social pressure to look good, especially for women.
It's not just the people using these treatments are the only ones at fault here. I don't think dentists & toothpaste manufacturers should put hydrogen peroxide in these tooth whitening treatments & toothpastes. I know that not everyone is willing to accept how they look but aren't there other less dangerous methods? Do the people know the dangers behind using these treatments in order to weigh up the pros & cons & make an informed decision? I, for 1 didn't even know that hydrogen peroxide was in these treatments until I watched a programme about it & I thought it was scary.
Yes, there are many ingredients in our consumer products and many other issues associated with said products, especially big commercial products, that manufacturers who live by selling them, plus special interest lobbying groups don't want us to know about. Your example is just a very minor one.
Classic big example: cover up by tobacco industry about cancer from cigarette smoking. They even used to hire medical pros who smoked in front of cameras thus testified with their own mean how "harmless" cigarette smoke was. The same with asbestos mining companies denying harmful effects of asbestos dust inhalations. They tried to procrastinate the legal actions hoping people will die before. The same with harmful effects of DDT.
The above are examples of yesteryear. Today is no different: Monsanto denies the bad environmental & health effects of using glyphosate and developing "roundup-ready" genetically modified crops. I don't even need to mention denial of global warming/climate change being the result of fossil fuel burning by coal mining companies and their special interest groups. Such cover-ups by those who profit from unhealthy activities, has always been and is an will always be part of our civilisation. For as long as the civilisation exists there will always be new cases of such cover-ups. That is, if civilisation survives climate change what presently looks unlikely. The latest cover-up of harmful effects of FF burning and procrastination of corrective action, by virtue of massive long term effects of current inaction, may be the final nail in the civilisation's coffin.
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I wouldn't call my example minor. People are using tooth whitening toothpastes or having dental tooth whitening products which have hydrogen peroxide in. Hydrogen peroxide is also known as hair bleach. No matter how well they rinse away these treatments some could accidentally be swallowed. Think of all the damage that could be caused.
At 1 time smoking was supposed to be good for you.
You always put global warming down to burning fossil fuels. I know this is part of the reason but it isn't the whole reason. There are other reasons why global warming occurs.
I have no clue about the first, first time hearing it.
About the second, I'm very familiar about it within computer science:
https://en.wikipedia.org/wiki/Computational_complexity_theory
It's essentially the theory that tries to classify different problems into "classes of complexity" so that given a problem and it's size (defined as the size of input data) we can expect the solution to the problem be obtained in finite time, or we can even estimate the time on a machine with given amount of memory and given processor speed/number of processors.
Roughly speaking, there exists 3 broad classes of problems: linear problems (resolvable in linear time or "near linear" time), polynomial problems (e.g. resolvable in square time) or exponential problems (that we sometimes call "untrackable"). We use deterministic Turing machine as a computational model here.
But this classification is not definite in the computational complexity world. In particular it hasn't been proved that exponential problems & polynomial problem are disjoint, I.e.: that exponential problems don't have polynomial solutions. It just happens that no algorithm has been found that can resolve exponential problems in polynomial time.
In practical terms, even polynomial algorithms (say cube time) are too slow for most problems of today when we have big amount of data (routinely billions of samples) as an input. That's because billion nanoseconds (a time of a single operation in modern computers) cubed equals 10^18 seconds which is many thousand years. You don't want to wait so long for your problem to be resolved. Whereas, if the problem is linear, for a input size of a billion samples, your computer can resolve it in roughly billion nanoseconds which is 1 second.
I looked up epigenetics. Apparently it's the study of inheritable changes in genetic expression which don't also show up in the D.N.A. sequence.
Thank you very much. I had an idea that complexity theory was about ways of classifying things into degrees of difficulty but I was unsure about the details of how it's done not only on a normal, everyday way but in a scientific way for the more complex things that scientists do everyday.That's fascinating. Thank you very much for sharing.
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This is going a bit off-topic I know but can someone please tell me this isn't serious?
I find it funny but scary that some people today still think the earth is flat. I've known the earth was an oblate spheroid for ages.
I find it funny but scary that some people today still think the earth is flat. I've known the earth was an oblate spheroid for ages.
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tented
Administrator
I just find it very hard to believe that anyone over early Middle school age (year 5 of school) wouldn't know that the earth is an oblate spheroid today. It's also scary. I think they all need to go back to Middle School.
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https://www.msn.com/en-gb/news/tech...tists-conclude/ar-AADHgJG?ocid=spartanntp_edu
Isn't this mind-blowing? What do you think? What a fancy name for it! I think if we had a word of the week competition that would definitely be 1 of the contenders.
Isn't this mind-blowing? What do you think? What a fancy name for it! I think if we had a word of the week competition that would definitely be 1 of the contenders.
Since no-one answered my question about what nidifugous meant & I thought somebody else might be interested I've found out for myself. Nidifugous refer to birds that flee the nest shortly after hatching. I knew nidiculous referred to birds which stayed in the nest until they were almost fully-grown. I should have known that nidifugous was going to be the opposite of nidiculous.
tented
Administrator
https://www.msn.com/en-gb/news/spot...omething-weird/ar-AAG2cmq?ocid=spartanntp_edu
What do you think of this?
What do you think of this?
tented
Administrator
It’s interesting. Also, I never knew the Soviets detonated nuclear bombs so powerful they ricocheted off the earth’s core.