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{0}

Nothing

- From absolute zero to cosmic oblivion -

Cat: SCI
Pub: 2013
#1423b

Jeremy Webb, et al.

14923u/18118r
Title

Nothing - From absolute zero to cosmic oblivion

無 - 絶対ゼロから宇宙の忘却まで

Index
Tag

Zero's rich concept; Big Bang; 0^-35 sec old; Secret life of the brain; Placebo power; Vacuum physics; the Casimir effect; Quantum mechanics; Absolute zero; Noble gas; BEC; Big Snap;

Why?
  • A very persuasive book written about time, just like scales fall from my eyes.
  • 芽から鱗が落ちるような説得力のある時間論である。
Original resume
Remarks

>Top 0. Introduction:

  • Nothing sounds suspiciously like an oxymoron.
    • Nothing has been a topic of discussion for more than 2,000 years:
    • the ancient Greeks had a lively disagreement about it.
    • Zero came into being in Babylonia around 300BC.
    • Zero emerged 1,000 years later when Indians fused that idea with an ancient symbol.
    • Another 400 years passed before it arrived in Europe
    • 17C it had gained acceptance.
  • Different aspect of reality:
    • Can something really come from nothing?
    • Why do some animals spend all day doing nothing?
    • What happens in our brain when we try to think about nothing?
  • Mysterious substance - void:
    • Ether
    • Vacuum of quantum theory
    • Absolute zero: the coldest cold. We haven't reached absolute zero and most likely never will.
    • nothings can be powerful
  • Zero is a concept rich in meaning and implication; it's no more nothing.

0. 序文:

  • ゼロの不思議さ
    • 2000年間も続く話題
    • 古代ギリシャのゼロ議論
    • バビロニアでのゼロ発明(300BC)
    • インドの貢献
    • 欧州に伝わるのに400年
    • 17Cになってやっと認知
  • ゼロもつ異なる現実性:
    • 無から本当に何かが生まれるか
    • 一部の動物は一日中 何もしないのはなぜか
    • ゼロを考える時、脳の中は?

 

  • ゼロのもつ豊富な概念

>Top 1. beginnings:

  • The Big Bang: A universe which was created out of nothing.
    • 13.82 billion years ago; everything - all matter, energy, even space and time came into being at that instant.
    • GUTs (Grand Unified Theories) are an attempt to show that three of the basic forces; the strong and weak nuclear forces and the electromagnetic force are no more than facets of a single superforce.
    • Boson; messenger particle
    • When the universe was 10^-35 seconds old; a messenger dubbed the X-boson.
    • Gravity split apart from the other three forces at about 10^-43 seconds after the big bang.
      • This is an exceedingly small interval of time; when the universe was young, things changed much mor rapidly.
      • The early universe was dominated by electromagnetic radiation; high-energy photons can change into particles of matter.
      • Photons so energetic, that colliding protons could produce particles out of radiant energy.
      • Before 10^-35 seconds old (unimaginable 10^28 ºC), we do not know.
      • today is 84 billion ly across.
  • 1/100 of a second old: it had cooled to be dominated by photons, electrons, positrons and neutrinos.
    • Neutrons and protons were around, tut were a very small contaminant.
    • There was roughly 10 billion +1 electrons for every 10 billion positrons.
    • After an orgy of annihilation, the universe was left with 10 billion photons for every electron. (The temperature had dropped to 1 billion ºC.
    • Protons and neutrons stayed close to each other long enough for the strong nuclear forces, which bind them together in the nuclei of atoms.
    • I particular, 2 protons and 2 neutrons could combine to form nuclei of helium.
    • 10 protons were left over for every helium nucleus that formed; these became the nuclei of hydrogen atoms.
    • When the temperature had cooled considerably, H and He nuclei picked up electrons to become stable atoms. (380,000 years after the big bang)
  • 3,000 ºC (expanded 1100 times):
    • Until the electrons had combined with H and He nuclei, photons could not travel far in a straight line; (The universe was opaque)
    • Energy levels of radiation, or photons, the universe fell below that of the matter.
    • From then on, the universe wad dominated by matter and by the force of gravity on the matter.
  • Carbon and Oxygen:
    • Hotter and denser conditions were needed;were created, billions years later, in the nuclear furnaces of stars.
    • About 9 billion years after the big bang, a yellow star was born towards the outer edge of a great spiral whirlpool of stars called the Milky Way. (our Sun)
  • >Top Secret life of the brain:
    • 1953 Louis Sokoloff; tried to find out how much energy the brain consumes during vigorous thought.
    • The brain was envisaged as being like a computer on standby.
    • Sokokoff's experiment provided that the brain enjoys a rich private life; only 2% of our body mas but devours 20% of the calories.
    • Thee is a huge amount of activity in the resting brain that has been largely unaccounted for.
      • neural dynamo of daydreaming
      • a more mysterious role, possibly selecting memories and knitting them seamlessly into a personal narrative.
    • PET (Positron Emission Topography) technique
    • Medial Prefrontal Cortex (PFC); evaluate things from a highly self-centred perspective of whether they're like to be good, bad or indifferent.
    • Hippocampus in limbic system: records and recalls autobiographical memories.
    • speculated that the brain with an inner rehearsal for considering future actions and choices.
      • Daydreaming: the brain engages in it whenever possible, breaking off only when it has to divert its limited supply of blood, oxygen and glucose to a more urgent task.
      • fMRI (functional Magnetic Resonance Imaging) technique
      • The default mode network (DMN) turns out to be disrupted in other maladies, including depression, ADHD (Attention Deficit Hyperactivity Disorder), autism and schizophrenia.
  • A brief history of nothing:
    • 1800 BC: Babylonians develop a positional number system
    • 300 BC: Babylonians invent a symbol for zero
    • 628 AD: Indian astronomer Brahmagupta introduced negative number - introducing zero as a crossing point between positive and negative values.
    • 800 AD: First evidence of the Hindu-Arabic zero in a decimal system
    • 1202 AD: Fibonacci introduces Hindu-Arabic system to western Europe.
    • 16C onwards: Cartesian geometry and calculus

1. いろいろな始まり:

  • ビッグバン:
    • 138.3億年前
    • 大統一理論
    • ボソン
  • $10^{-35}$秒経過後の宇宙

 

  • 1/100秒経過後
    • 100億+1の電子と100億の陽電子

 

 

 

 

 

 

 

 

 

 

 

 

  • 大脳の不思議な動き:
  • 前頭前皮質:
    • 前頭前皮質内側部
    • 認知行動
    • 成果の予測
    • 社会的コントロール


  • 海馬:

 

 

  • DMN (Default Mode Network) vs. TPN (Task Positive Network)

 

 

  • バビロニアのゼロ(300BC)
    $1×60^2 +0×60 +4 =3604$
  • babylonianzero
>Top

2. Mysteries:

  • The desire to solve mysteries or understand anomalies in the world around us is the driving force of science.
  • Four mysteries, unsolved or partly solved, that will lead to new understanding:
    1. The day time began
    2. Placebo power
    3. Wastes of space
    4. Banishing consciousness
  • The day time began: direct evidences are:
    • The universe is still expanding today.
    • The existence of a pervasive heat radiation that is neatly explained as the fading afterglow of the big bang.
    • The relative abundance of the chemical elements, which can be correctly accounted for in terms of nuclear processes in the hot dense phase that followed the big bang.
    • Usual questions:
      • What caused the big bang to happen?
      • Where is the center of the explosion?
      • Where is the edge of the universe?
      • Why didn't the big bang turn into a black hole?
    • The idea that space can stretch, or be warped, is a central prediction of Einstein.
    • The spec from which space emerges is not located in anything. It is not an object surrounded by emptiness.
    • It appears instantaneously from nothing and immediately expands.
    • It resembles the apex of a cone, where the fabric of the cone tapers to an infinitely sharp point and ceases. It is here that space and time begin.
    • There was no such epoch as 'before the big bang,' because time began with the big bang.
    • Stephen Hawking: 'What lies north of the north Pole?'
    • Our brains are hardwired for us to think in terms of cause and effect.
    • Models of universe involving many big bangs, perhaps even an infinite number of them.
    • The region we have been calling the universe is viewed as but one 'bubble' of space within an infinite system of bubbles.
    • Quantum physics introduced the new feature that the separate identities of space and time can be smeared or blurred on an ultramicroscopic scale.
  • >Top Placebo power:
    • The placebo effect has been called the power of nothing.
    • Real action of a drug; the very act of administering a drug activate a complex cascade of biochemical events in the patient's brain. A drug may interact with these expctation-activated molecules, confounding the interpretation of results.
    • The strength of these effects can be influenced by expectation.
    • Placebos have also been shown to trigger the release of dopamine in people with Parkinson's disease.
    • individual neurons in the brains of Parkinson's patients respond to a salt solution in the same way as they do to a genuine drug designed to relieve tremors.
  • Wastes of space?:
    • Vomeronasal organ (VNO); mainly detect pheromones; role of reproduction and social behavior.
    • Goose bumps: in birds or mammals with feather, fur or spines, this creates a layer of insulating warm air in cold snap, or a reason for a predator to think twice before attacking.
    • Darwin's point: takes the form of a cartilaginous node or bump on the rim of outer ear, which is thought to be the vestige of a joint that allowed the top part of the ancestral ear to swivel or flop down over the opening to the ear.
    • The tail bone: human coccyx, a vestige of the mammalian tail, which has taken on a modified function, notably as an anchor point for the muscles that hold the anus in place.
    • Wisdom teeth: Most primates have wisdom teeth (the third molars), but a few species have not. When the body size of mammals reduces rapidly, their jaws become too small to house all their teeth, and overcrowding eventually results in selection for fewer or smaller teeth.
  • Banishing consciousness:
    • Consciousness may often be thought of as an all-or-nothing quality - either awake or not - but there are different levels of anesthesia:
      1. Light-headedness:
        →Being drank
      2. Amnesia
      3. Ominousness: failure to respond to command
        → Sleep
      4. Failure to respond to pain: need mechanical ventilation to maintain breathing
        → Unconsciousness due to brain damage/vegetable state/coma
    • EEG (Electroencephalograph sensors):
    • the deepest levels of anesthesia, the primary sensory cortex was the only region to respond to the electric shock.
    • Long-distance communication seems to be blocked, so the brain cannot build the global workspace. It's like the message is reaching the mailbox, but no one is picking it up.

2. ミステリー:

  • ミステリーは科学の発展力
  • 4つの未解決なミステリー
    1. 時間の始まり
    2. プレシボの力
    3. 空間の消費
    4. 意識の始まり

 

  • 初日の始まり

 

 




  • プラシボの力

 

 

 

  • 空間の消耗

 

 

 

 

 

 

  • 意識の喪失

 

 

 

  • 感覚麻痺のレベル
>Top

3. Making sense of it all:

  • Four great inventions in 17C singled out profound impact on the way humanity views reality.
    1. Telescope: helped us to understand the solar system and the earth is not at its center.
    2. Microscope: opened up a rich yet previously invisible micro world and paved the way for modern medicine.
    3. Pendulum clock: was our first accurate timekeeper and a fundament of modern society.
    4. Vacuum pump: its impact is less obvious; possibly because changes in pressure are more difficult to appreciate than images: vacuum become critical in shaping our view of matter and the way we live.
  • Vacuum physics:
    • Evangelist Torricelli in 1644: the height of mercury in the tube fell to 76- mm leaving a gap at the top that could only be a vacuum.
    • Sprengel improved the attainable pressure to reach 10^-5 mbar.
    • Thomas Edison needed a way to stop the filaments in his incandescent light bulbs from burning up.
    • 1898: Wilhelm Röntgen used vacuum tubes to create the first X-rays, as did Heinrich Hertz in his discovery of the photoelectric effect.
    • 1905: Wolfgang Gaede's pump; and 1915 he presented the first diffusion pump, still a reliable industrial workhorse today.
    • second half of 20C: semiconductor making needed reliable, fast, clean vacuum pups and chambers.
    • Nuclear and particle physics, both demanded high vacuums.
    • 1957 turbo-molecular pump; runs at 30,00 to 75,000 revolutions a minute, can reach pressures as low as about 10^-10 mbar.
    • Can we reach perfect vacuum?: No.
    • Cryopumping; works by cooling exposed areas so they adsorb or freeze out any remaining gas molecules; are cooled by liquid nitrogen; creating 10^-33 mbar.
  • CERN:
    • to store antimatter; must be kept away from ordinary particles.
    • antimatter can be stored for months under such conditions.
    • about 100 atoms per cubic cm, corresponds to 10^-16 mbar to avoid contact between particle and antiparticles.
  • Busy doing nothing:
    • By any measure some animals are lazy. why do they do nothing?
    • giant python, which lies around for months waiting fro its next meal and then rests in the bushes for weeks doing nothing but digesting.; 0.032 ml of oxygen per gram of body weight per hour.
    • More surprisingly, the metabolism of some of the most immobile creatures may be working as hard as a race-horse on the big day.
    • Metabolic rate; 0.3 ml of oxygen per gram of body weight per hour.
    • Walking can double this, sprinting can raise it as much as tenfold.
    • Snake starts with the very low resting rate of about 0.032 ml of oxygen per gram of body weight per hour.
    • Salamander is by necessity a sedentary creature.; it doesn't just do nothing to survive - it also sees nothing.
      • It takes a great deal of energy to maintain vision, because there is a rapid turnover of cells in the retina and cornea.
  • The hole story:
    • Absences of electron acting for all the world like positive charges - and moving the wrong way in magnetic field.
    • In silicon crystals, all electron are bound. But add boron atoms, which have one fewer binding electrons, and holes are created. Electrons leap between these holes to generate a current. The holes effectively flow in the opposite direction.
    • The p-b-p transistor, in which a region of electron excess was sandwiched between two hole-dominated areas.
  • Zero tolerance:
    • Zero is a born troublemaker.
    • Power: 5^0 x 5^2 must qual to 5^(0+2) =25; Therefore 5^0 must equal 1.
    • Factorial: is the number of ways to arrange n things in order.
      • 3! = 3 x 2!
      • 2! = 2 x 1!
      • 1! = 1 x 0! Since 1!=1, this leads to 0!=1.
    • Nicolas Bourbaki: θ: Set theory needs θ for the same reason that arithmetic needs 0.
      • the empty set is unique; We define 1 to be the set of whose only member is the empty set, {θ}. This is not the same as the empty set, because it has one member, where the empty set has none. That member happens to be the empty set, but there is one of it.
      • The key step is to define the number 2; the set {θ, {θ}}; which is the same as {0,1}.
      • Define 3 as {0, 1, 2}, a set with three members. Everything traces back to the empty set: 3 is {θ, {θ},{θ, {θ}}} and 4 is {θ, {θ},{θ, {θ}}, {θ, {θ},{θ, {θ}}}}

3. 筋が通ること:

  • 17Cの4大発明
    1. 望遠鏡
    2. 顕微鏡
    3. 振り子時計
    4. 真空ポンプ:地味だがその後の科学の発展に貢献

 

 

  • 真空物理学:
    • トリチェリから
    • 低温ポンプ

 

 

 

 

 

  • CERN:
    • 反物質の保管方法

 

 

 

  • 何もしないという多忙
    • 代謝率
>Top

4. Surprises:

  • The turbulent life of empty space:
    • "Nature abhors a vacuum." in Greek philosophy some 2500 years ago.
    • Empty space is richer than a mere absence of things.; it plays an indispensable part in much of modern physics.
    • Isaac Newton, like Aristotle, thought that the space between bodies must be filled with a medium; it must be invisible, but also frictionless.
    • Gottfried Leibniz disagreed; if the stars were to vanish, so would the force; there was no need for an invisible medium in between.
    • During 19C, the nature of empty space began to occupy the thoughts of physicists in a new context; the mystery of how one charged body feels the pull of another, or how tow magnets sense each other's presence.
    • Michael Faraday; explained the regions of influence - fields - around them, which other bodies experienced as a force.
    • Luminiferous aether, or ether; but the speed of light should depend on the speed and direction of Earth motion.
    • 1905 Einstein;a body's motion must always be judge relative to another body. Electric and magnetic fields exist, but not longer as strains in any space-filling medium. Their strength and direction, and the forces they exert, change with the motion of the observer such that the speed of light is always measure to be the same.
  • Vacuum packed:
    • Nothing will come of nothing: Shakespeare epigram
    • 1948: the Casimir effect (named after Hendrik Casimir); the notion that a perfect vacuum, the very definition of nothingness in the physical world, contains a latest power that can be harnessed to move objects and make stuff.
    • According to quantum theory, even a perfect vacuum is filled with wave-like fields that fluctuate constantly, producing a legion of ephemeral particles that continually pop out of nowhere only to disappear again, filling the vacuum with what's called 'zero-point energy'.
  • >Top quantum mechanics:
    • Quantum mechanics; at the level of atoms, the clockwork predictability of the classic Newtonian universe broke down; at any given moment its position and motion will be uncertain.
    • Although the field strength of the fluctuations average to zero, the energy does not, because an electric field's energy is independent of its direction.
    • Waves also have characteristic of particles, so the quantum vacuum is often depicted as a sea of short-lived particles - photons for the electromagnetic field, gravitons for the gravitational field, and so on - popping out of nowhere and disappearing again.
    • Wave or particle, what one gets is a picture of the vacuum that is reminiscent of the ether.
    • In the event that the pressure of the quantum vacuum is negative, the gravitational effect is also negative. That is, negative-pressure quantum-vacuum fluctuations serve to create a repulsive or anti-gravitating, force.
    • Einstein had predicted that empty space would have such an anti-gravitational effect in 1917, before quantum mechanics.
    • Sure enough, far-off supernovae that a huge anti-gravitation force is causing the entire universe to expand faster and faster; ether has recently been remanded dark energy. (Brian Schemidt, etc.)
    • A proper understanding of dark energy's strength and properties will probably require new physics, perhaps coming from string theory or others.
    • the notion that space is a mere void with no physical properties is no longer tenable.
    • the fate of the universe lies in the properties of the vacuum; depending on how dark energy works.

4. 驚き:

  • 真空空間の変遷
    • ギリシャ
    • ニュートン
    • ライプニッツ
    • 19C
    • ファラディー
    • イーサー
    • アインシュタイン

 

  • 量子力学
    • 不確定性原理
    • 量子力学的な真空とは
    • 反引力
    • イーサーとダークエネルギー

 

 

 

  • カシミール効果
    • ヘンドリック・カシミール
    • 零点エネルギー

 

 

  • 宇宙の運命は真空の属性 (エネルギー)次第。
>Top

5. Voyages of discovery:

  • Absolute zero:
    • Absolute zero is an idea and unattainably perfect state of coldness.
    • Daniel Fahrenheit used the freezing temperature of brine as a zero because it was the coldest temperature he could achieve.
    • Kelvin scale starts at 0 K. The melting temperate of ice (0º C) is at 273.15K.
    • Louis-Paul Cailetet liquefied oxygen at -183 ºC and nitrogen at -196 ºC
    • In 1898 James Dewar: liquefied hydrogen at -250 ºC.
    • In 1908 Heike Kamerlingh Onnes: liquefied helium at 4.2 K.
    • Also Onnes discovered that at very low temperature metals become superconductive.
    • By sucking out helium molecules were remove and the liquid cooled even further; 2.17 K.
    • The lighter atoms o 3He condensed at 3.2 K, instead of 4.2 K of 4He.
    • Dilution refrigerator; 3He to behave like a gas - effectively evaporating into a 4He vacuum. With this set-up, matter can be cooled to below 0.001 K.
    • Tungsten became superconducting at 0012 K and 3He itself became a superfluid at just 0003 K.
    • We can cool smaller amounts of material (just a million atoms or so) using laser light; this has slowed atoms from moving at around 1m/sec at 1mK to roughly 1 mm/s at nK.
  • Third Law of Thermodynamics: "The entropy of a system approaches a constant value as the temperature approaches absolute zero."
    • a target to be cooled in thermal contact with a cooler substance, typically a recirculating fluid.
    • to get heart flowing out of a target that you want to reach absolute zero, the fluid coolant would have to be older than - K to begin with!; it is clearly impossible to make molecules move slower than not moving at all.
  • >Top Noble gas:
    • Xenon-133: This is a fission product of uranium that doesn't react with anything else ad has a half-life of five days, so should hang around long enough to be detected. A positive result would have been definitive.; as Hitler didn't have the bomb.
    • Discovery of argon; opened the door to the other noble gases, was serendipitous.
    • Obey the Biblical injunction; seek and ye shall find. But seek not to find that for which ye seek.
    • The first noble-gas compound; mixing red gaseous PtF6 and colorless xenon supplied the answer; Bartless found it to have the formula XePtF6 - xenon hexafluoroplatinate.

5. 発見の旅:

  • 絶対零度:

 

 

 

 

  • 熱力学第三法則:
    エントロピーは絶対零度ですべて等しくなる。
    • 絶対零度に近づいても絶対零度にはならない。
    • 絶対零度以下の物体と接触できない
    • 断熱膨張でも無限に膨張させることは不可能
    • 体内に蓄積しにくい
    • 医療検査用吸引ガスに利用

 

 

  • 希ガス
    • キセノン133
    • U235やPu239の核分裂生成物
    • 核実験や原発事故の証拠
>Top

6. Conclusions:

  • Conclusions in science are strange in that they are not for ever.
    • Jocelyn Bell Burnell discovered pulsars; "Nothing is static, nothing is final, everything is held provisionally."
    • Theories can be useful even when they are not correct. The prevailing theory prevails precisely because it describes reality better than any other.
  • Human activity:
    • We were built to be active, but the way our environment has changed and the way we live our lives had led us to become inactive.
    • Physical inactivity is killing us. If physical inactivity was packaged and sold as a product, it would nee to carry a health warning label.
  • BEC (Bose-Eistein Condensate):
    • Superfluids, superconductor an supersolid owe their bizarre behavior to the formation of a sort of superatom inside them, known as a BEC.
    • In 2011, Chandra X-ray telescope showed that the core of a neutron star called Cassiopeia A, 11K ly away, is a superfluid. One teaspoon of neutron star weight 6B tons and the intense pressure is enough to squeeze the core into a BEC. Neutron star contains a portion of protons too, which also form BEC.
  • Long-term forecast:
    • Things will become rather uncomfortable in about 6B years, when the sub wells to become a red giant, boiling the oceans away and possibly even swallowing Earth. The our star will exhaust its nuclear fuel and shrink into a white dwarf roughly the size of Earth, leaving our old planet (if it still exists) cold enough to be covered in nitrogen ice.
    • At least the view will be lovely; gas blown into space by the red giant will be energized by ultraviolet rays from the white dwarf, so for while Earth will be surrounded by a glowing multicolored nebula.
    • Our galaxy is in for a rough time too. Andromeda collide in as little as 3b years. For a while the merger will create a brilliant, elaborate hybrid galaxy, as steamers of star are flung outwards, and most of the loose gas in both galaxies is compressed to form bright new stars.
    • Our collision with Andromeda will have a spectacular climax At the the center of the Milky Way is a giant black hole (more than 3M times mass of the sun). Another in Andromeda is probably ten times the size. The two black holes will settle towards the center of the new galaxy and there they will spiral together and eventually merge.
    • The energy release will be tremendous, sending out a blast of light and X-rays, and a pulse of gravitational waves that will squeeze and stretch every star and planet.
  • Big Snap:
    • Everything would disintegrate.
    • Acceleration will soon steal most of the universe away, as the increasing expansion of space carries other galaxies beyond our view. Their light will no longer reach us.
    • The we will be all alone, the observable universe reduced to our one elliptical galaxy.
    • All nuclear-powered stars will have gone out.
    • A little faint infrared radiation will come from stars called brown dwarfs, which are too small to ignite fusion in their cores.
    • Other stars will be reduced to dense, dead remnants - black holes, neutron stars and aging white dwarfs, slowly dimming to black. Our sun will become one of these black dwarfs; a single crystal of carbon, like an ultra-dense diamond.
    • Now our observable universe is reduced to a diaspora of dead stars, loosely centered on a massive black hole surrounded by a cloud of dark matter.

6. 結語:

  • 人間の活動

 

  • BEC:

 

  • 長期予測:
    • 太陽系の運命
    • アンドロメダ銀河との衝突

 

 

 

  • ビックスナップ
Comment
  • Etymology of zero came from Arabic 'sifr' (nothing).
  • Cipher came from the same 'sifr'; cipher has the meaning of a secret or disguised way of writing.
  • Decipher means convert a text written in code into normal language.
  • Thus zero has scent of lots of secrets.
  • Anyway I could read through the story of infinite in a finite time.
  • Zeroの語源は、アラビア語の'sifr'に由来。。
  • ここからcipher 暗号化する、decipher 暗号解読するの意味が発生した。
  • Zeroには、ともかく多くの秘密の匂いがする。
  • ともかく無限の話を有限時間に読み終えることができた。

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