nhaliday + thermo   52

An adaptability limit to climate change due to heat stress
Despite the uncertainty in future climate-change impacts, it is often assumed that humans would be able to adapt to any possible warming. Here we argue that heat stress imposes a robust upper limit to such adaptation. Peak heat stress, quantified by the wet-bulb temperature TW, is surprisingly similar across diverse climates today. TW never exceeds 31 °C. Any exceedence of 35 °C for extended periods should induce hyperthermia in humans and other mammals, as dissipation of metabolic heat becomes impossible. While this never happens now, it would begin to occur with global-mean warming of about 7 °C, calling the habitability of some regions into question. With 11–12 °C warming, such regions would spread to encompass the majority of the human population as currently distributed. Eventual warmings of 12 °C are possible from fossil fuel burning. One implication is that recent estimates of the costs of unmitigated climate change are too low unless the range of possible warming can somehow be narrowed. Heat stress also may help explain trends in the mammalian fossil record.

Trajectories of the Earth System in the Anthropocene: http://www.pnas.org/content/early/2018/07/31/1810141115
We explore the risk that self-reinforcing feedbacks could push the Earth System toward a planetary threshold that, if crossed, could prevent stabilization of the climate at intermediate temperature rises and cause continued warming on a “Hothouse Earth” pathway even as human emissions are reduced. Crossing the threshold would lead to a much higher global average temperature than any interglacial in the past 1.2 million years and to sea levels significantly higher than at any time in the Holocene. We examine the evidence that such a threshold might exist and where it might be.
study  org:nat  environment  climate-change  humanity  existence  risk  futurism  estimate  physics  thermo  prediction  temperature  nature  walls  civilization  flexibility  rigidity  embodied  multi  manifolds  plots  equilibrium  phase-transition  oscillation  comparison  complex-systems  earth 
august 2018 by nhaliday
Theory of Self-Reproducing Automata - John von Neumann
Fourth Lecture: THE ROLE OF HIGH AND OF EXTREMELY HIGH COMPLICATION

Comparisons between computing machines and the nervous systems. Estimates of size for computing machines, present and near future.

Estimates for size for the human central nervous system. Excursus about the “mixed” character of living organisms. Analog and digital elements. Observations about the “mixed” character of all componentry, artificial as well as natural. Interpretation of the position to be taken with respect to these.

Evaluation of the discrepancy in size between artificial and natural automata. Interpretation of this discrepancy in terms of physical factors. Nature of the materials used.

The probability of the presence of other intellectual factors. The role of complication and the theoretical penetration that it requires.

Questions of reliability and errors reconsidered. Probability of individual errors and length of procedure. Typical lengths of procedure for computing machines and for living organisms--that is, for artificial and for natural automata. Upper limits on acceptable probability of error in individual operations. Compensation by checking and self-correcting features.

Differences of principle in the way in which errors are dealt with in artificial and in natural automata. The “single error” principle in artificial automata. Crudeness of our approach in this case, due to the lack of adequate theory. More sophisticated treatment of this problem in natural automata: The role of the autonomy of parts. Connections between this autonomy and evolution.

- 10^10 neurons in brain, 10^4 vacuum tubes in largest computer at time
- machines faster: 5 ms from neuron potential to neuron potential, 10^-3 ms for vacuum tubes

https://en.wikipedia.org/wiki/John_von_Neumann#Computing
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april 2018 by nhaliday
Ultimate fate of the universe - Wikipedia
The fate of the universe is determined by its density. The preponderance of evidence to date, based on measurements of the rate of expansion and the mass density, favors a universe that will continue to expand indefinitely, resulting in the "Big Freeze" scenario below.[8] However, observations are not conclusive, and alternative models are still possible.[9]

Big Freeze or heat death
Main articles: Future of an expanding universe and Heat death of the universe
The Big Freeze is a scenario under which continued expansion results in a universe that asymptotically approaches absolute zero temperature.[10] This scenario, in combination with the Big Rip scenario, is currently gaining ground as the most important hypothesis.[11] It could, in the absence of dark energy, occur only under a flat or hyperbolic geometry. With a positive cosmological constant, it could also occur in a closed universe. In this scenario, stars are expected to form normally for 1012 to 1014 (1–100 trillion) years, but eventually the supply of gas needed for star formation will be exhausted. As existing stars run out of fuel and cease to shine, the universe will slowly and inexorably grow darker. Eventually black holes will dominate the universe, which themselves will disappear over time as they emit Hawking radiation.[12] Over infinite time, there would be a spontaneous entropy decrease by the Poincaré recurrence theorem, thermal fluctuations,[13][14] and the fluctuation theorem.[15][16]

A related scenario is heat death, which states that the universe goes to a state of maximum entropy in which everything is evenly distributed and there are no gradients—which are needed to sustain information processing, one form of which is life. The heat death scenario is compatible with any of the three spatial models, but requires that the universe reach an eventual temperature minimum.[17]
physics  big-picture  world  space  long-short-run  futurism  singularity  wiki  reference  article  nibble  thermo  temperature  entropy-like  order-disorder  death  nihil  bio  complex-systems  cybernetics  increase-decrease  trends  computation  local-global  prediction  time  spatial  spreading  density  distribution  manifolds  geometry  janus 
april 2018 by nhaliday
Antinomia Imediata – experiments in a reaction from the left
https://antinomiaimediata.wordpress.com/lrx/
So, what is the Left Reaction? First of all, it’s reaction: opposition to the modern rationalist establishment, the Cathedral. It opposes the universalist Jacobin program of global government, favoring a fractured geopolitics organized through long-evolved complex systems. It’s profoundly anti-socialist and anti-communist, favoring market economy and individualism. It abhors tribalism and seeks a realistic plan for dismantling it (primarily informed by HBD and HBE). It looks at modernity as a degenerative ratchet, whose only way out is intensification (hence clinging to crypto-marxist market-driven acceleration).

How come can any of this still be in the *Left*? It defends equality of power, i.e. freedom. This radical understanding of liberty is deeply rooted in leftist tradition and has been consistently abhored by the Right. LRx is not democrat, is not socialist, is not progressist and is not even liberal (in its current, American use). But it defends equality of power. It’s utopia is individual sovereignty. It’s method is paleo-agorism. The anti-hierarchy of hunter-gatherer nomads is its understanding of the only realistic objective of equality.

...

In more cosmic terms, it seeks only to fulfill the Revolution’s side in the left-right intelligence pump: mutation or creation of paths. Proudhon’s antinomy is essentially about this: the collective force of the socius, evinced in moral standards and social organization vs the creative force of the individuals, that constantly revolutionize and disrupt the social body. The interplay of these forces create reality (it’s a metaphysics indeed): the Absolute (socius) builds so that the (individualistic) Revolution can destroy so that the Absolute may adapt, and then repeat. The good old formula of ‘solve et coagula’.

Ultimately, if the Neoreaction promises eternal hell, the LRx sneers “but Satan is with us”.

https://antinomiaimediata.wordpress.com/2016/12/16/a-statement-of-principles/
Liberty is to be understood as the ability and right of all sentient beings to dispose of their persons and the fruits of their labor, and nothing else, as they see fit. This stems from their self-awareness and their ability to control and choose the content of their actions.

...

Equality is to be understood as the state of no imbalance of power, that is, of no subjection to another sentient being. This stems from their universal ability for empathy, and from their equal ability for reason.

...

It is important to notice that, contrary to usual statements of these two principles, my standpoint is that Liberty and Equality here are not merely compatible, meaning they could coexist in some possible universe, but rather they are two sides of the same coin, complementary and interdependent. There can be NO Liberty where there is no Equality, for the imbalance of power, the state of subjection, will render sentient beings unable to dispose of their persons and the fruits of their labor[1], and it will limit their ability to choose over their rightful jurisdiction. Likewise, there can be NO Equality without Liberty, for restraining sentient beings’ ability to choose and dispose of their persons and fruits of labor will render some more powerful than the rest, and establish a state of subjection.

https://antinomiaimediata.wordpress.com/2017/04/18/flatness/
equality is the founding principle (and ultimately indistinguishable from) freedom. of course, it’s only in one specific sense of “equality” that this sentence is true.

to try and eliminate the bullshit, let’s turn to networks again:

any nodes’ degrees of freedom is the number of nodes they are connected to in a network. freedom is maximum when the network is symmetrically connected, i. e., when all nodes are connected to each other and thus there is no topographical hierarchy (middlemen) – in other words, flatness.

in this understanding, the maximization of freedom is the maximization of entropy production, that is, of intelligence. As Land puts it:

https://antinomiaimediata.wordpress.com/category/philosophy/mutualism/
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march 2018 by nhaliday
Equilibrium thermodynamics - Wikipedia
Equilibrium Thermodynamics is the systematic study of transformations of matter and energy in systems in terms of a concept called thermodynamic equilibrium. The word equilibrium implies a state of balance. Equilibrium thermodynamics, in origins, derives from analysis of the Carnot cycle. Here, typically a system, as cylinder of gas, initially in its own state of internal thermodynamic equilibrium, is set out of balance via heat input from a combustion reaction. Then, through a series of steps, as the system settles into its final equilibrium state, work is extracted.

In an equilibrium state the potentials, or driving forces, within the system, are in exact balance. A central aim in equilibrium thermodynamics is: given a system in a well-defined initial state of thermodynamic equilibrium, subject to accurately specified constraints, to calculate, when the constraints are changed by an externally imposed intervention, what the state of the system will be once it has reached a new equilibrium. An equilibrium state is mathematically ascertained by seeking the extrema of a thermodynamic potential function, whose nature depends on the constraints imposed on the system. For example, a chemical reaction at constant temperature and pressure will reach equilibrium at a minimum of its components' Gibbs free energy and a maximum of their entropy.

Equilibrium thermodynamics differs from non-equilibrium thermodynamics, in that, with the latter, the state of the system under investigation will typically not be uniform but will vary locally in those as energy, entropy, and temperature distributions as gradients are imposed by dissipative thermodynamic fluxes. In equilibrium thermodynamics, by contrast, the state of the system will be considered uniform throughout, defined macroscopically by such quantities as temperature, pressure, or volume. Systems are studied in terms of change from one equilibrium state to another; such a change is called a thermodynamic process.
nibble  wiki  reference  concept  conceptual-vocab  explanation  definition  physics  stat-mech  thermo  equilibrium  summary 
november 2017 by nhaliday
Autoignition temperature - Wikipedia
The autoignition temperature or kindling point of a substance is the lowest temperature at which it spontaneously ignites in normal atmosphere without an external source of ignition, such as a flame or spark. This temperature is required to supply the activation energy needed for combustion. The temperature at which a chemical ignites decreases as the pressure or oxygen concentration increases. It is usually applied to a combustible fuel mixture.

The time {\displaystyle t_{\text{ig}}} {\displaystyle t_{\text{ig}}} it takes for a material to reach its autoignition temperature {\displaystyle T_{\text{ig}}} {\displaystyle T_{\text{ig}}} when exposed to a heat flux {\displaystyle q''} {\displaystyle q''} is given by the following equation:
nibble  wiki  reference  concept  metrics  identity  physics  thermo  temperature  time  stock-flow  phys-energy  chemistry  article  street-fighting  fire  magnitude  data  list 
november 2017 by nhaliday
Europa, Enceladus, Moon Miranda | West Hunter
A lot of ice moons seem to have interior oceans, warmed by tidal flexing and possibly radioactivity.  But they’re lousy candidates for life, because you need free energy; and there’s very little in the interior oceans of such system.

It is possible that NASA is institutionally poor at pointing this out.
west-hunter  scitariat  discussion  ideas  rant  speculation  prediction  government  dirty-hands  space  xenobio  oceans  fluid  thermo  phys-energy  temperature  no-go  volo-avolo  physics  equilibrium  street-fighting  nibble  error  track-record  usa  bio  eden  cybernetics  complex-systems 
september 2017 by nhaliday
All models are wrong - Wikipedia
Box repeated the aphorism in a paper that was published in the proceedings of a 1978 statistics workshop.[2] The paper contains a section entitled "All models are wrong but some are useful". The section is copied below.

Now it would be very remarkable if any system existing in the real world could be exactly represented by any simple model. However, cunningly chosen parsimonious models often do provide remarkably useful approximations. For example, the law PV = RT relating pressure P, volume V and temperature T of an "ideal" gas via a constant R is not exactly true for any real gas, but it frequently provides a useful approximation and furthermore its structure is informative since it springs from a physical view of the behavior of gas molecules.

For such a model there is no need to ask the question "Is the model true?". If "truth" is to be the "whole truth" the answer must be "No". The only question of interest is "Is the model illuminating and useful?".
thinking  metabuch  metameta  map-territory  models  accuracy  wire-guided  truth  philosophy  stats  data-science  methodology  lens  wiki  reference  complex-systems  occam  parsimony  science  nibble  hi-order-bits  info-dynamics  the-trenches  meta:science  physics  fluid  thermo  stat-mech  applicability-prereqs  theory-practice  elegance  simplification-normalization 
august 2017 by nhaliday
Controversial New Theory Suggests Life Wasn't a Fluke of Biology—It Was Physics | WIRED
First Support for a Physics Theory of Life: https://www.quantamagazine.org/first-support-for-a-physics-theory-of-life-20170726/
Take chemistry, add energy, get life. The first tests of Jeremy England’s provocative origin-of-life hypothesis are in, and they appear to show how order can arise from nothing.
news  org:mag  profile  popsci  bio  xenobio  deep-materialism  roots  eden  physics  interdisciplinary  applications  ideas  thermo  complex-systems  cybernetics  entropy-like  order-disorder  arrows  phys-energy  emergent  empirical  org:sci  org:inst  nibble  chemistry  fixed-point  wild-ideas  multi 
august 2017 by nhaliday
[1705.03394] That is not dead which can eternal lie: the aestivation hypothesis for resolving Fermi's paradox
If a civilization wants to maximize computation it appears rational to aestivate until the far future in order to exploit the low temperature environment: this can produce a 10^30 multiplier of achievable computation. We hence suggest the "aestivation hypothesis": the reason we are not observing manifestations of alien civilizations is that they are currently (mostly) inactive, patiently waiting for future cosmic eras. This paper analyzes the assumptions going into the hypothesis and how physical law and observational evidence constrain the motivations of aliens compatible with the hypothesis.

http://aleph.se/andart2/space/the-aestivation-hypothesis-popular-outline-and-faq/

simpler explanation (just different math for Drake equation):
Dissolving the Fermi Paradox: http://www.jodrellbank.manchester.ac.uk/media/eps/jodrell-bank-centre-for-astrophysics/news-and-events/2017/uksrn-slides/Anders-Sandberg---Dissolving-Fermi-Paradox-UKSRN.pdf
http://marginalrevolution.com/marginalrevolution/2017/07/fermi-paradox-resolved.html
Overall the argument is that point estimates should not be shoved into a Drake equation and then multiplied by each, as that requires excess certainty and masks much of the ambiguity of our knowledge about the distributions. Instead, a Bayesian approach should be used, after which the fate of humanity looks much better. Here is one part of the presentation:

Life Versus Dark Energy: How An Advanced Civilization Could Resist the Accelerating Expansion of the Universe: https://arxiv.org/abs/1806.05203
The presence of dark energy in our universe is causing space to expand at an accelerating rate. As a result, over the next approximately 100 billion years, all stars residing beyond the Local Group will fall beyond the cosmic horizon and become not only unobservable, but entirely inaccessible, thus limiting how much energy could one day be extracted from them. Here, we consider the likely response of a highly advanced civilization to this situation. In particular, we argue that in order to maximize its access to useable energy, a sufficiently advanced civilization would chose to expand rapidly outward, build Dyson Spheres or similar structures around encountered stars, and use the energy that is harnessed to accelerate those stars away from the approaching horizon and toward the center of the civilization. We find that such efforts will be most effective for stars with masses in the range of M∼(0.2−1)M⊙, and could lead to the harvesting of stars within a region extending out to several tens of Mpc in radius, potentially increasing the total amount of energy that is available to a future civilization by a factor of several thousand. We also discuss the observable signatures of a civilization elsewhere in the universe that is currently in this state of stellar harvesting.
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may 2017 by nhaliday
chemistry - Is it possible to make an alloy that melts at low temperatures and solidifies at high temperatures? - Worldbuilding Stack Exchange
I'm sure this is outside of the range of temperatures you were interested in, but in the spirit of "truth is stranger than fiction," Helium-3 actually does this.
nibble  q-n-a  stackex  trivia  chemistry  physics  thermo  state  temperature  weird  phase-transition 
may 2017 by nhaliday
Interview Greg Cochran by Future Strategist
https://westhunt.wordpress.com/2016/08/10/interview/

- IQ enhancement (somewhat apprehensive, wonder why?)
- ~20 years to CRISPR enhancement (very ballpark)
- cloning as an alternative strategy
- environmental effects on IQ, what matters (iodine, getting hit in the head), what doesn't (schools, etc.), and toss-ups (childhood/embryonic near-starvation, disease besides direct CNS-affecting ones [!])
- malnutrition did cause more schizophrenia in Netherlands (WW2) and China (Great Leap Forward) though
- story about New Mexico schools and his children (mostly grad students in physics now)
- clever sillies, weird geniuses, and clueless elites
- life-extension and accidents, half-life ~ a few hundred years for a typical American
- Pinker on Harvard faculty adoptions (always Chinese girls)
- parabiosis, organ harvesting
- Chicago economics talk
- Catholic Church, cousin marriage, and the rise of the West
- Gregory Clark and Farewell to Alms
- retinoblastoma cancer, mutational load, and how to deal w/ it ("something will turn up")
- Tularemia and Stalingrad (ex-Soviet scientist literally mentioned his father doing it)
- germ warfare, nuclear weapons, and testing each
- poison gas, Haber, nerve gas, terrorists, Japan, Syria, and Turkey
- nukes at https://en.wikipedia.org/wiki/Incirlik_Air_Base
- IQ of ancient Greeks
- history of China and the Mongols, cloning Genghis Khan
- Alexander the Great vs. Napoleon, Russian army being late for meetup w/ Austrians
- the reason why to go into Iraq: to find and clone Genghis Khan!
- efficacy of torture
- monogamy, polygamy, and infidelity, the Aboriginal system (reverse aging wives)
- education and twin studies
- errors: passing white, female infanticide, interdisciplinary social science/economic imperialism, the slavery and salt story
- Jewish optimism about environmental interventions, Rabbi didn't want people to know, Israelis don't want people to know about group differences between Ashkenazim and other groups in Israel
- NASA spewing crap on extraterrestrial life (eg, thermodynamic gradient too weak for life in oceans of ice moons)
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march 2017 by nhaliday
Which one would be easier to terraform: Venus or Mars? - Quora
what Greg Cochran was suggesting:
First, alternatives to terraforming. It would be possible to live on Venus in the high atmosphere, in giant floating cities. Using a standard space-station atmospheric mix at about half an earth atmosphere, a pressurized geodesic sphere would float naturally somewhere above the bulk of the clouds of sulfuric acid. Atmospheric motions would likely lead to some rotation about the polar areas, where inhabitants would experience a near-perpetual sunset. Floating cities could be mechanically rotated to provide a day-night cycle for on-board agriculture. The Venusian atmosphere is rich in carbon, oxygen, sulfur, and has trace quantities of water. These could be mined for building materials, while rarer elements could be mined from the surface with long scoops or imported from other places with space-plane shuttles.
q-n-a  qra  physics  space  geoengineering  caltech  phys-energy  magnitude  fermi  analysis  data  the-world-is-just-atoms  new-religion  technology  comparison  sky  atmosphere  thermo  gravity  electromag  applications  frontier  west-hunter  wild-ideas  🔬  scitariat  definite-planning  ideas  expansionism 
february 2017 by nhaliday
How do food manufacturers calculate the calorie count of packaged foods? - Scientific American
The original method used to determine the number of kcals in a given food directly measured the energy it produced.The food was placed in a sealed container surrounded by water--an apparatus known as a bomb calorimeter. The food was completely burned and the resulting rise in water temperature was measured. This method is not frequently used today.
q-n-a  news  org:sci  popsci  food  nutrition  measurement  phys-energy  physics  thermo  org:mag  explanation  metabolic  methodology  fire  heavy-industry 
february 2017 by nhaliday
Orthogonal — Greg Egan
In Yalda’s universe, light has no universal speed and its creation generates energy.

On Yalda’s world, plants make food by emitting their own light into the dark night sky.
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february 2017 by nhaliday
Energy of Seawater Desalination
0.66 kcal / liter is the minimum energy required to desalination of one liter of seawater, regardless of the technology applied to the process.
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february 2017 by nhaliday
Edge.org: Q-Bio, the most interesting recent [scientific] news
Applied mathematicians and theoretical physicists are rushing to develop new sophisticated tools that can capture the other, non-genomic challenges posed in trying to quantify biology. One of these challenges is that the number of individuals in a community may be large, but not as large as there are molecules of gas in your lungs, for example. So the traditional tools of physics based on statistical modeling have to be upgraded to deal with the large fluctuations encountered, such as in the number of proteins in a cell or individuals in an ecosystem. Another fundamental challenge is that living systems need an energy source.

They are inherently out of thermodynamic equilibrium, and so cannot be described by the century-old tools of statistical thermodynamics developed by Einstein, Boltzmann and Gibbs. Stanislaw Ulam, a mathematician who helped originate the basic principle behind the hydrogen bomb, once quipped, “Ask not what physics can do for biology. Ask what biology can do for physics.” Today, the answer is clear: biology is forcing physicists to develop new experimental and theoretical tools to explore living cells in action.
bio  trends  science  interdisciplinary  physics  thermo  org:edge  giants  einstein  boltzmann  stat-mech  equilibrium  complex-systems  cybernetics 
november 2016 by nhaliday
Faster than Fisher | West Hunter
There’s a simple model of the spread of an advantageous allele:  You take σ, the typical  distance people move in one generation, and s,  the selective advantage: the advantageous allele spreads as a nonlinear wave at speed  σ * √(2s).  The problem is, that’s slow.   Suppose that s = 0.10 (a large advantage), σ = 10 kilometers, and a generation time of 30 years: the allele would take almost 7,000 years to expand out 1000 kilometers.

...

This big expansion didn’t just happen from peasants marrying the girl next door: it required migrations and conquests. This one looks as if it rode with the Indo-European expansion: I’ll bet it started out in a group that had domesticated only horses.

The same processes, migration and conquest, must explain the wide distribution of many geographically widespread selective sweeps and partial sweeps. They were adaptive, all right, but expanded much faster than possible from purely local diffusion. We already have reason to think that SLC24A5 was carried to Europe by Middle Eastern farmers; the same is probably true for the haplotype that carries the high-activity ergothioniene transporter and the 35delG connexin-26/GJB2 deafness mutation. The Indo-Europeans probably introduced the T-13910 LCT mutation and the delta-F508 cystic fibrosis mutation, so we should see delta-F508 in northwest India and Pakistan – and we do !

https://westhunt.wordpress.com/2014/11/22/faster-than-fisher/#comment-63067
To entertain a (possibly mistaken) physical analogy, it sounds like you’re suggested a sort genetic convection through space, as opposed to conduction. I.e. Entire masses of folks, carrying a new selected variant, are displacing others – as opposed to the slow gene flow process of “girl-next-door.” Is that about right? (Hopefully I haven’t revealed my ignorance of basic thermodynamics here…)

Has there been any attempt to estimate sigma from these time periods?

Genetic Convection: https://westhunt.wordpress.com/2015/02/22/genetic-convection/
People are sometimes interested in estimating the point of origin of a sweeping allele: this is probably effectively impossible even if diffusion were the only spread mechanism, since the selective advantage might well vary in both time and space. But that’s ok, since population movements – genetic convection – are real and very important. This means that the difficulties in estimating the origin of a Fisher wave are totally insignificant, compared to the difficulties of estimating the effects of past colonizations, conquests and Völkerwanderungs. So when Yuval Itan and Mark Thomas estimated that 13,910 T LCT allele originated in central Europe, in the early Neolithic, they didn’t just go wrong because of failing to notice that the same allele is fairly common in northern India: no, their whole notion was unsound in the first place. We’re talking turbulence on steroids. Hari Seldon couldn’t figure this one out from the existing geographic distribution.
west-hunter  genetics  population-genetics  street-fighting  levers  evolution  gavisti  🌞  selection  giants  nibble  fisher  speed  gene-flow  scitariat  stylized-facts  methodology  archaeology  waves  frontier  agri-mindset  analogy  visual-understanding  physics  thermo  interdisciplinary  spreading  spatial  geography  poast  multi  volo-avolo  accuracy  estimate  order-disorder  time  homo-hetero  branches  trees  distribution  data  hari-seldon  aphorism  cliometrics  aDNA  mutation  lexical 
november 2016 by nhaliday
The Day Before Forever | West Hunter
Yesterday, I was discussing the possibilities concerning slowing, or reversing aging – why it’s obviously possible, although likely a hard engineering problem. Why partial successes would be valuable, why making use of the evolutionary theory of senescence should help, why we should look at whales and porcupines as well as Jeanne Calment, etc., etc. I talked a long time – it’s a subject that has interested me for many years.

But there’s one big question: why are the powers that be utterly uninterested ?

https://www.facebook.com/ISIInc/videos/vb.267919097102/641005449680861/?type=2&theater
The Intercollegiate Studies Institute and the Abagail Adams Institute host a debate between Peter Thiel and William Hurlbut. Resolved: Technology Should Treat Death as an Enemy

https://westhunt.wordpress.com/2017/07/03/the-best-things-in-life-are-cheap-today/
What if you could buy an extra year of youth for a million bucks (real cost). Clearly this country ( or any country) can’t afford that for everyone. Some people could: and I think it would stick in many people’s craw. Even worse if they do it by harvesting the pineal glands of children and using them to manufacture a waxy nodule that forfends age.

This is something like the days of old, pre-industrial times. Back then, the expensive, effective life-extender was food in a famine year.

https://westhunt.wordpress.com/2017/04/11/the-big-picture/
Once upon a time, I wrote a long spiel on life extension – before it was cool, apparently. I sent it off to an interested friend [a science fiction editor] who was at that time collaborating on a book with a certain politician. That politician – Speaker of the House, but that could be anyone of thousands of guys, right? – ran into my spiel and read it. His immediate reaction was that greatly extending the healthy human life span would be horrible – it would bankrupt Social Security ! Nice to know that guys running the show always have the big picture in mind.

Reminds me of a sf story [Trouble with Lichens] in which something of that sort is invented and denounced by the British trade unions, as a plot to keep them working forever & never retire.

https://westhunt.wordpress.com/2015/04/16/he-still-has-that-hair/
He’s got the argument backward: sure, natural selection has not favored perfect repair, so says the evolutionary theory of of senescence. If it had, then we could perhaps conclude that perfect repair was very hard to achieve, since we don’t see it, at least not in complex animals.* But since it was not favored, since natural selection never even tried, it may not be that difficult.

Any cost-free longevity gene that made you live to be 120 would have had a small payoff, since various hazards were fairly likely to get you by then anyway… And even if it would have been favored, a similar gene that cost a nickel would not have been. Yet we can afford a nickel.

There are useful natural examples: we don’t have to start from scratch. Bowhead whales live over 200 years: I’m not too proud to learn from them.

Lastly , this would take a lot of work. So what?

*Although we can invent things that evolution can’t – we don’t insist that all the intermediate stages be viable.

https://westhunt.wordpress.com/2013/12/09/aging/
https://westhunt.wordpress.com/2014/09/22/suspicious-minds/

doesn't think much of Aubrey de Gray: https://westhunt.wordpress.com/2013/07/21/of-mice-and-men/#comment-15832
I wouldn’t rely on Aubrey de Gray.

It might be easier to fix if we invested more than a millionth of a percent of GNP on longevity research. It’s doable, but hardly anyone is interested. I doubt if most people, including most MDs and biologists, even know that it’s theoretically possible.

I suppose I should do something about it. Some of our recent work ( Henry and me) suggests that people of sub-Saharan African descent might offer some clues – their funny pattern of high paternal age probably causes the late-life mortality crossover, it couldn’t hurt to know the mechanisms involved.

Make Room! Make Room!: https://westhunt.wordpress.com/2015/06/24/make-room-make-room/
There is a recent article in Phys Rev Letters (“Programed Death is Favored by Natural Selection in Spatial Systems”) arguing that aging is an adaptation – natural selection has favored mechanisms that get rid of useless old farts. I can think of other people that have argued for this – some pretty smart cookies (August Weismann, for example, although he later abandoned the idea) and at the other end of the spectrum utter loons like Martin Blaser.

...

There might could be mutations that significantly extended lifespan but had consequences that were bad for fitness, at least in past environments – but that isn’t too likely if mutational accumulation and antagonistic pleiotropy are the key drivers of senescence in humans. As I said, we’ve never seen any.

more on Martin Blaser:
https://westhunt.wordpress.com/2013/01/22/nasty-brutish-but-not-that-short/#comment-7514
This is off topic, but I just read Germs Are Us and was struck by the quote from Martin Blaser ““[causing nothing but harm] isn’t how evolution works” […] “H. pylori is an ancestral component of humanity.”
That seems to be the assumption that the inevitable trend is toward symbiosis that I recall from Ewald’s “Plague Time”. My recollection is that it’s false if the pathogen can easily jump to another host. The bulk of the New Yorker article reminded me of Seth Roberts.

I have corresponded at length with Blaser. He’s a damn fool, not just on this. Speaking of, would there be general interest in listing all the damn fools in public life? Of course making the short list would be easier.

https://westhunt.wordpress.com/2013/01/18/dirty-old-men/#comment-64117
I have corresponded at length with Blaser. He’s a damn fool, not just on this. Speaking of, would there be general interest in listing all the damn fools in public life? Of course making the short list would be easier.
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november 2016 by nhaliday
Overcoming Bias : A Future Of Pipes
The future of computing, after about 2035, is adiabatic reservable hardware. When such hardware runs at a cost-minimizing speed, half of the total budget is spent on computer hardware, and the other half is spent on energy and cooling for that hardware. Thus after 2035 or so, about as much will be spent on computer hardware and a physical space to place it as will be spent on hardware and space for systems to generate and transport energy into the computers, and to absorb and transport heat away from those computers. So if you seek a career for a futuristic world dominated by computers, note that a career making or maintaining energy or cooling systems may be just as promising as a career making or maintaining computing hardware.

We can imagine lots of futuristic ways to cheaply and compactly make and transport energy. These include thorium reactors and superconducting power cables. It is harder to imagine futuristic ways to absorb and transport heat. So we are likely to stay stuck with existing approaches to cooling. And the best of these, at least on large scales, is to just push cool fluids past the hardware. And the main expense in this approach is for the pipes to transport those fluids, and the space to hold those pipes.

Thus in future cities crammed with computer hardware, roughly half of the volume is likely to be taken up by pipes that move cooling fluids in and out. And the tech for such pipes will probably be more stable than tech for energy or computers. So if you want a stable career managing something that will stay very valuable for a long time, consider plumbing.

Will this focus on cooling limit city sizes? After all, the surface area of a city, where cooling fluids can go in and out, goes as the square of city scale , while the volume to be cooled goes as the cube of city scale. The ratio of volume to surface area is thus linear in city scale. So does our ability to cool cities fall inversely with city scale?

Actually, no. We have good fractal pipe designs to efficiently import fluids like air or water from outside a city to near every point in that city, and to then export hot fluids from near every point to outside the city. These fractal designs require cost overheads that are only logarithmic in the total size of the city. That is, when you double the city size, such overheads increase by only a constant amount, instead of doubling.
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august 2016 by nhaliday

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