Wikipedia:Reference desk/Archives/Science/2017 September 10

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September 10

Standard-Model Extension

Can someone explain this in simpler terms? Am I right in assuming that if Lorentz symmetry is broken, things can/do have an absolute velocity, position, orientation etc.? What is "dynamical" symmetry breaking? 93.139.41.72 (talk) 02:23, 10 September 2017 (UTC)

It means that if there existed some background static and spatially homogeneous vector or tensor field, it would be possible to measure absolute velocity and orientation relative to it. Such a field can appear as a result of some interaction within an initially Lorentz invariant theory - dynamically. So, Lorentz violation is fictional because the theory remains Lorentz invariant. For instance, if you are inside a large volume and there is a constant and homogeneous magnetic field inside it created by currents at the large distance from the observer, one may (without any information about what happens at large distances) conduct some experiments and conclude that there is indeed a preferable direction. Ruslik_Zero 18:34, 10 September 2017 (UTC)

Just in case you missed it: dynamical symmetry breaking 92.18.64.254 (talk) 20:21, 10 September 2017 (UTC)

If the tech level/population/GDP/Milankovitch factors/Sun/biosphere etc. stopped evolving in 1749 how long would it take for CO2 to rise 1ppm?

Would the anthropogenic fire/cow flatulence etc. carbon just go in the carbon sinks and the CO2 ppm in the atmosphere would never rise? Would this cause any ocean pH changes measurable with 2017 instruments? (our 2017, they're still using horses and buggies in this timeline's 2017 remember) Sagittarian Milky Way (talk) 03:08, 10 September 2017 (UTC)

The CO₂ level would level off at a lower level, but what that level would be and when it would level off I can't say. StuRat (talk) 03:13, 10 September 2017 (UTC)

• Too many variables, I think. Civilizations at that tech level tended to grow in population until the available land was all under cultivation. Examples include Italy, Greece, India, China, and England. If we project forward from 1749, humanity would have cleared the forests everywhere by now (except possibly for parts of Africa which are protected by diseases). The effect on CO₂ levels is hard to analyze. Also that tech level still allow for coal mining, which would be economically attractive as the forests disappeared. This was already happening in England by then.-Arch dude (talk) 04:52, 10 September 2017 (UTC)

The Black Death in Eurasia followed by the huge mass deaths in South and then North America from smallpox and other diseases are thought to have been one of the major contributors to the beginning of the Little Ice Age because they caused CO₂ to drop due to reforestation. The reforestation would be pretty rapid but the effect on temperature would be much slower, there would be a drop in CO₂ and then it would rise to near its former level as in 1400 over a couple of hundred years. So yes I believe in 1749 you'd be looking at CO₂ rising again so I guess they should only have taken about twenty years to rise 1ppm at that time. I'd say 1749 was about the beginning of the modern world so yes you are cutting out a lot of stuff never mind other factors that contributed to the Little Ice Age. One would really need a climate scientist to model it to get something reasonable but there are a lot of unknowns. Dmcq (talk) 11:48, 10 September 2017 (UTC)

Not an answer to your question, but memorably Svante Arrhenius estimated around the year 1900 that it would take about 3000 years to increase CO2 concentrations by 50%. Of course, we found many new uses of fossil fuels since 1900. Dragons flight (talk) 19:27, 10 September 2017 (UTC)

Did he think of all the important forcings before calculating? (like water vapor also being a greenhouse gas) Sagittarian Milky Way (talk) 07:20, 12 September 2017 (UTC)

He probably did not think of all the important forcings (probably we don't even know all, depending on how you define "important" and at what time frames you are looking), but yes, he did include water vapour feedback and ice/albedo feedback (of course limited by the computational resources of the day), and his result is essentially still squarely near the middle of modern estimates. --Stephan Schulz (talk) 07:31, 12 September 2017 (UTC)

Not really, he was off be a factor of 2 from the present-day preferred value. That's close, and quite good for his time, but it is probably a stretch to say he is in the middle. Dragons flight (talk) 08:31, 12 September 2017 (UTC)

Yes, you are right - I misremembered his result as 3° when it was 5-6°C, which is still not implausible, but at the upper limit of current estimates. Sorry. --Stephan Schulz (talk) 08:47, 12 September 2017 (UTC)

Virus vaccines

Thanks for the input! Nyttend (talk) 03:28, 10 September 2017 (UTC)

Measles

According to File:Measles vaccination coverage world.svg (data from 2010), Austria's vaccination rate was lower than that of countries like Chad, Iraq, and the Democratic Republic of the Congo. Why is their rate so low?

According to the german wiki:

In Österreich werden zwei Teilimpfungen gegen Masern-Mumps-Röteln ab dem vollendeten 9. Lebensmonat mit einem Mindestabstand von vier Wochen empfohlen. Bei Schuleintritt bzw. mit vollendetem 12. Lebensjahr soll der Impfstatus (Impfpass) kontrolliert werden. Fehlende Impfungen können in jedem Lebensalter kostenlos nachgeholt werden.[73] Eine Erhebung des Gesundheitsministeriums aus 2016 ergab, dass über 95 Prozent der 6-jährigen Kinder zumindest einmal gegen Masern geimpft sind. Bei den 2- bis 5-jährigen Kindern beträgt die Durchimpfungsrate jedoch nur 92 Prozent, zudem sind etwa 10 Prozent davon nur einfach anstatt zweimal geimpft.[74]☂[75]

Of the 6 year olds, 95% have received the vaccine at least once, according to 2016 data. Of the 2 to 5 year olds, 92% have received the vaccine at least once, 82% twice. It doesn't seem as dramatic as the map suggests. Maybe confusion over the exact meaning of vaccination (once or twice) or the age at which vaccination rate is measured. PiusImpavidus (talk) 09:45, 10 September 2017 (UTC)

The vaccination rate could have changed. New WHO data seems to confirm this. Ruslik_Zero 18:15, 10 September 2017 (UTC)

[1] from 2015 using data from the WHO from an unknown period suggests Austria is "At a 75 percent immunization rate, Austria comes in just above Afghanistan, but below even Yemen and Sierra Leone." [2] suggests a big issue for Austria is the number of unvaccinated older adults. Those who never caught the disease and were never vaccinated. Although it also mentions the general challenges vaccinating adults who were never vaccinated, which does highlight a point. Even if your vaccination rates are now fairly high (albeit 95% actually doesn't sound that high to me even if it's significantly higher than the other figures) for children, if it was low for whatever reason for a while it's only going to slowly increase unless you're able to vaccinate unvaccinated adults. Otherwise you have to wait for them to die off or have such a high population growth that they are only a tiny percentage of your population. Nil Einne (talk) 18:17, 11 September 2017 (UTC) Clarified: 08:48, 12 September 2017 (UTC)

From [3] it sounds like measles is a small problem for them - 75 cases in 8.6 million people a year, in hotspots. The vaccine came out in the 1960s but there was not much retroactive vaccination of children who had already grown up and not caught it. Wnt (talk) 22:56, 12 September 2017 (UTC)

Chicken pox

According to [4], approximately 1% of individuals vaccinated with chicken pox will develop symptoms similar to that of an ordinary low-grade infection, and it's possible for them to develop shingles late in life. Have any cases of shingles been observed in those who were vaccinated without developing symptoms of a chicken pox infection? I'm not clear whether it's possible just in those who develop symptoms or in all those who are vaccinated.

Varicella vaccine gives some information. I'm pretty sure it's possible, because the varicella vaccine is a live vaccine. You're being deliberately infected, just with a weakened strain of the virus, and varicella, once acquired, hangs around for life in your cells (as do all of its family, the herpesviruses), and its reactivation is what causes shingles. If anything, I'd think people who have a reaction should be less likely to develop shingles, because it means their immune systems were more strongly activated by the vaccine. --47.138.161.183 (talk) 05:52, 10 September 2017 (UTC)

You can read this. Ruslik_Zero 18:19, 10 September 2017 (UTC)

Going to have to disagree a 'little bit' with Ruslik_Zero . The immune system is complex. Chickenpox like measles is reasonably contagious but the primary immune system (for want of a better phase) in some individuals prevents the virus from even getting hold and invoking an infection where the virus can turn the hosts body cells in to virus factories. In those individuals the virus can't lay dormant, for it to develop latter into singles. Please Note: The jury is still out. Yet, it appears that if an individual does not contract chickenpox naturally nor show a reaction to the inoculation then they do not go on to develop shingles. Another observation is that regardless of whether chickenpox infection was acquired naturally or by immunization – it doesn’t provide life long protection in those without natural resistance. So, the reason why singles is now becoming so much more common in older people is being put down to the fact that they are no longer having their immune system boosted naturally by coming into contact with children that have a full blown chickenpox infections who are shredding off billions of viruses. Thus requiring old inocululyees to require booster shot latter in life. It appears that if as a child, the individual showed no reaction then there is no proven epidemiological reason that a MD should insist on a booster – other than for financial reasons. Aspro (talk) 14:32, 11 September 2017 (UTC)

I am not sure where these ideas come from? I am not aware of any such publications. You have probably failed to read the paper that I linked to above. There is no such thing as natural immunity to HHV3. Any individual that comes into contact with the virus will be infected and the virus will establish its presence in the dorsal root ganglia. In many individual this primary infection can be overt (in the form of chickenpox) but in some it is silent. However any infected individual can later develop herpes zoster. If you had read that paper, you would have found that even among immunized 1/3 of cases of herpes zoster is due to the wild virus, not one from the vaccine. So, silent infections happen all the time. As to children serving as natural boosters to older persons, this no any agreement here. Infected individuals can self-boost their immunity and this self-boosting may be more important than any boosting from an external source. Ruslik_Zero 18:45, 11 September 2017 (UTC)

Can see where your coming from. At school, we are taught that for an individual to have 'immunity' they need antibodies (acquired either by previous infections or through the placenta or via inoculations) to fight off a future infection. This is a gross over simplification of the immune system. For many decades now it has been known that interferon and interleukin I I and other immune responses can make an individual a non-viable host to some viruses. Interferon is species specific and if an individual has an interferon type to make that individual a non-viable host for said virus- then that virus can not invade the cells and take them over in order to replicate. Because the virus can't survive, replicate and cause an infection, the B-cells are not called upon to produce antibodies. Likewise, the afore said HHV3 virus can not survive in the dorsal root ganglia to later cause shingles. Thus, such an individual with an antibody titer of zero for chickenpox can be exposed multiple times to chickenpox and not get infected (nor pass it on). This sort of in-depth of understanding doesn’t have to be taught to doctors for the obvious reasons that they never have to treat these individual for those viral diseases for which they are naturally and genetically immune too. To underline 'non-viable' host with an extreme example. [Killer mousepox virus raises bioterror fears. Your antibody titer should be zero for this virus too. Yet, if you have understood the above, you will fear not (fingers-crossed). Aspro (talk) 13:29, 12 September 2017 (UTC)

You again failed to cite any source claiming that there are humans who are not susceptible to HHV3 infection. It is true that mice are not susceptible to HHV3 because viruses are often species specific but different humans belong to the same species. And your understanding of the human immune system is incomplete - B-cells and antibodies is just one its many branches. Ruslik_Zero 08:52, 13 September 2017 (UTC)

This has had me searching for not science papers, because they only focus on a tiny bits and don't give an overall picture – which wont help you – unless you're prepared to do an awful lot of reading. Found this though: The Defending Army It is a pretty old book now, yet has 9 respected consultant editors (who papers appear on goggle scholar). It covers all of what I have been saying and is aimed towards giving the layperson an understanding of the wonders of our immune system -so is easy to follow. It also ends with few chapters on how the state of mind has been found to effect the immune system. Skipped through a few pages and it goes into details that your general physician wont have be taught about even today. Wish I had come across a book like this, forty years ago. So thanks for asking and getting me to search for sources of simple explanations.Aspro (talk) 16:00, 13 September 2017 (UTC)

Irma in Florida

I am wondering about the hurricanes. There is an article in Wikipedia that tries to explain it all.[5]. It seems the following it clear. The earth rotation linear velocities differences at different latitudes create cyclones. Had the earth been a cylinder no cyclones could have happened, right? Heat coming from the ocean is needed too. It is an enormous angular momentum after all. How come Irma hit Cuba, touched it a bit and turned North to Florida? Why? Where is the force that did it? Logically it would have to continue to the East coast of Mexico.

In the Atlantic the hurricanes travel West, in the Pacific they seem to travel East and in the Indian subcontinent they definitely travel East. Why?

In Jupiter the red spot (a hurricane) is said to have existed for 350 years. How did they determine it? --AboutFace 22 (talk) 21:08, 10 September 2017 (UTC)

Answering just the last question: see Great Red Spot. It has been seen since 1830, and is believed to be the same spot that was first observed over 350 years ago, but the record of observations is not continuous. It might be only about 190 years old, or it might be thousands of years old. --69.159.60.147 (talk) 21:23, 10 September 2017 (UTC)

Hurricane Irma's recurvature is largely due to forces exerted on the system by other areas of atmospheric pressure, particularly a high-pressure "ridge" over the North Atlantic known as the Bermuda High. See this Washington Post article for a summary.

Atlantic, Indian, and Pacific (and South Atlantic) tropical cyclones all predominantly travel westbound, not eastbound, though recurvature is not uncommon in all basins as systems move away from the equatorial trade winds, as per our article.

Jupiter's Great Red Spot is dated via continuous observation for ~190 years, and via inference from observations of a similar phenomenon (commonly assumed to be the same formation) dating back to 1665, as per our article. — Lomn 21:24, 10 September 2017 (UTC)

And if you happen to be in Jupiter, Florida, you have to worry about both. :-) StuRat (talk) 21:53, 10 September 2017 (UTC)