标记档案: 感悟

Sensory and Physical Worlds

Animals have different sensory capabilities compared to us humans. Cats, 例如, can hear up to 60kHz, while the highest note we have ever heard was about 20kHz. 似乎, we could hear that high a note only in our childhood. 所以, if we are trying to pull a fast one on a cat with the best hifi multi-channel, Dolby-whatever recording of a mouse, we will fail pathetically. It won’t be fooled because it lives in a different sensory world, while sharing the same physical world as ours. There is a humongous difference between the sensory and physical worlds.

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理查德·费曼 — 能有多大,我们知道?

我们打​​开我们的眼睛, 我们看到的世界, 我们辨别图案. 我们推论, 正式; 我们使用和合理性和数学的理解和描述的一切. 多少钱才能真正知道, 虽然?

为了说明我的意思, 让我用一个比喻. 我希望我的想象力,想出它, 但它是理查德·费曼谁做. 他, 顺便说说, 够古怪的比较 物理与性.

继续阅读

Why did Federer Lose?

I am a Federer fan. His inevitable decline has been a source of grief for me. When it comes to shot selection, imagination and pure magical talent, there isn’t another tennis player who could ever hold a candle to him. Why did he have to go and lose in the second round of Wimbledon? It damn near broke my heart.

Roger Federer行, we all know the answer. He is getting too old. But he is only 31, and has to be in terrific shape. I am pushing fifty and can still put in a couple of hours of vigorous badminton. 肯定, weekend badminton is no world class tennis, and the effects of aging are very different. Still…, I wish he would stick around a bit longer.

A few months ago, I listened to a series of interesting lectures on the effects of aging on our perception and sensory processes. One thing new that I learned there was that we all have a sixth sense, in addition to sight, hearing, touch, taste and smell. It is the kinesthetic, muscle feedback, which is the sense that allows you to apply just the right amount of pressure, 例如, when braking your car, or holding a baby. You may lose this sense when you get angry and break the glass you are holding, if we are to believe Hollywood movies. In certain games, this sense can make an enormous difference. I had a friend who was a pool shark. He once told me that at the top of his game, he could feel the tiny nicks and scratches on the cue ball through the cue stick in his hand. When I knew him, he was well past his prime, but he could still call shots like bank off the point of the side pocket, and double kiss into the corner pocket. And make them. So I believe him and Eddie Felson (The Hustler) when he says the cue stick, when he holds it, has nerves. I bet Federer could feel the seams of the tennis ball and the amount of spin he was putting on them through the strings and the grip of his racket.

Age blunts the sharpness of all of your senses. The most obvious is your sight. In your forties, you have to hold your smart phone farther and farther away from your face to read the tiny screen. 在一些点, your hand is not long enough and you end up using reading glasses — reluctantly at first, but more readily as the years roll by and the images get blurrier. Apparently you lose your sensitivity to high pitched sound as well. So teenagers can download ringtones that their parents and teachers are deaf to. But the first sense to go is the muscle feedback, which begins to decline in your teens. 这, 显然, is the reason why the Olympic gymnasts are all teenagers. By the time they are in their twenties, this sense of theirs is already too weak to keep them competitive at that level. I guess it is this sense that has deserted Roger Federer as well.

Frederer’s brand of tennis with its finesse and artistry demanded more of this sense. His opponents tend to hit flatter and harder. I read somewhere that they use stiffer rackets for this purpose, and can hold Federer behind the baseline. The champion stubbornly refuses to switch to this style and this kind of rackets. May be he is getting a bit too old. Reminds me of Bjorn Borg, when he attempted a mini come-back with his wooden racket.

自由意志 — 的幻觉?

如果我们能够让自己的事实感到惊讶,我们的非物质空灵的头脑可以在物理世界中真的开动的东西, 我们会发现自己想知道 — 我们真的有自由意志? 如果自由意志仅仅是在电活动在我们的大脑模式, 如何可以这种图案会导致在物理世界中的变化和重排? 难道说这种模式是真正造成自由意志的幻觉?

逻辑奥卡姆剃刀的形式应该指导我们在后者的可能性. 但逻辑并不适用于许多或大多数生命的基本假设, 其回答到一组不同的规则. 他们回答的神话, 总和的无形的知识和智慧从过去流传下来, 从古代, 被遗忘的大师们通过我们的老师和民间传说和我们说话, 通过我们的语言的结构和我们的思想背景, 并通过我们的存在和意识感非常基础. 在神话告诉我们,我们有自由意志, 和了后者的逻辑是无力打破这种观念. 所以,这可能是因为该流出来我的笔到这个记事本,后来到您的计算机屏幕这些话都是预定的,我只好写下来,然后. 但它肯定不是我的感觉. 我觉得好像我在这里可以删除任何字. Heck, 我可以删除整个后,如果我想.

在逻辑侧, 我将描述这使人们对我们的自由意志概念无疑是一个实验. 从神经科学, 我们知道,有大约一半的时刻之间的第二的时间滞后 “我们” 作出决定的那一刻,我们意识到这一点. 该时间延迟引发的谁走,因为决策的问题, 在没有我们的意识, 目前尚不清楚,这个决定确实是我们的. 在实验装置测试该现象, 主题是挂接到记录他的大脑活动的计算机 (脑电图). 然后受试者被要求做他的选择的时候有意识地决定移动无论是右手还是左手. 的右侧或左侧的选择也达主题. 计算机总是检测拍摄对象将其用手移动约半秒前的主题是意识到自己的打算. 然后,计算机可以命令主体来移动手 — 一个订单,该主题将无法违抗. 受试者是否有自由意志在这种情况下,?

事实上, 我写了这 在我的书, 和 贴在这里 前一段时间. 在该职位, 我补充说,自由意志可能是我们大脑的实际行动后制造. 换句话说, 真正的行动本能地发生, 和决策的意识引入到我们作为一种事后的意识. 我的一些读者指出,被​​不知情的决定是不一样的有超过它没有自由意志. 例如, 当你驾驶, 你采取了一系列的决策并没有真正意识到他们的. 这并不意味着,这些决定不是你. 好点子, 但是否真的有意义调用决定你当你没有在它的任何控制, 即使如果你做你会采取同样的决定? 如果有什么飞进你的眼睛, 你会退缩,闭上你的眼睛. 良好的生存本能和反射. 但考虑到你无法控制它, 它是你的自由意志的一部分?

一个更精细的例子来自催眠暗示. 我听到这个故事由约翰·塞尔讲座之一 — 一名男子被催眠指示字回应 “德国” 爬行在地板上. 催眠会议结束后, 当该男子清醒想必行使他的自由意志, 触发字是在一个对话中. 该男子突然说像, “我只记得, 我需要重塑我的房子, 而这些瓷砖很好看. 介意我细看?” 和爬行在地板上. 难道他做他自己的意志? To him, yes, 但要休息, 现在.

所以, 我们怎么知道为确保我们的自由意志的感觉是不是我们的大脑是在犯下一个精心制作的骗局 “我们” (这意味着什么!)

现在,我实际上推的说法远一点. 不过,仔细想想, 哪有spaceless, 无质量, 材料少的实体是我们的意图使在现实世界中我们身边真正的变革? 在写这篇文章, 我怎么可以打破物理定律在各地相当独立它们当前的状态搬东西只是因为我想?

是自由意志的附带现象 — 事情出现后 - 事实? 一个很好的类比是,泡沫乘着海浪沙滩上. 泡沫可能会想, “哦,我的上帝, 什么样的苦日子! 我不得不长途所有这些大浪来回. 我生命中的每一天, 没有休息, 没有休假!” 但是,这并不是什么回事. 波浪只是左右晃动, 和泡沫恰好出现. 是我们生活只是沿着自己的道路注定了移动, 虽然我们, 像附带现象泡沫, 认为我们控制和自由意志?

什么是太空?

这听起来像一个奇怪的问题. 我们都知道空间是什么, 这是在我们身边. 当我们打开我们的眼睛, 我们看到它. 如果眼见为实, 那么问题 “什么是空间?” 确实是一个奇怪的1.

说句公道话, 我们没有真正看到的空间. 我们只看到我们假定物体在空间. 宁, 我们定义空间,不管它是持有或包含的对象. 这是竞技场里的物体做他们的事, 我们的经验背景. 换句话说, 经验预先假定空间和时间, 并提供了基础背后的科学理论目前流行的解释的世界观.

虽然不是很明显, 这个定义 (或者假设或谅解) 空间配备了一个哲学的行李 — 即现实主义. 现实主义者的观点是占主导地位的Einstien的理论目前的了解,以及. 但爱因斯坦自己可能没有盲目地接受现实. 否则为什么他会说:

为了从现实的抓地力打破, 我们要切向接近问题. 做到这一点的一种方法是通过研究神经科学和视线认知基础, 它毕竟提供了有力的证据,以空间的真实性. 空间, 大体上, 与视觉体验相关. 另一种方法是研究其他感官体验相关性: 什么是声音?

当我们听到的东西, 我们听到的是什么, 自然, 声音. 我们经历了基调, 强度和时间变化,告诉我们很多关于谁说话, 什么破等. 但是,即使剥离后,所有的额外财富增加了我们的大脑的体验, 最基本的经验仍然是一个 “声音。” 我们都知道它是什么, 但我们不能在条件比这更基本的解释.

现在,让我们来看看负责审理的感官信号. 正如我们所知道, 这些是在由一个振动体使压缩和凹陷在周围的空气产生的空气压力波. 就像在一个池塘中的涟漪, 这些压力波传​​播的几乎所有方向. 他们拾起我们的耳朵. 通过巧妙的机制, 耳朵进行频谱分析和发送电信号, 这大致对应于波的频谱, 我们的大脑. 注意, 到目前为止, 我们有一个振动体, 聚束和空气分子扩散, 和的电信号,它包含有关空气分子的图案信息. 我们没有还音.

声音的经验是神奇的大脑进行. 它转换编码的空气压力波图案以色调的表示和声音的丰富度的电信号. 声音是不是一个振动体的固有性质或倒下的树, 这是我们的大脑选择代表振动或方式, 更精确, 编码该压力波的频谱的电信号.

没有有意义调用声音我们听觉的感官输入内部认知的表示? 如果你同意, 那么现实本身就是我们的感觉输入我们的内部表示. 这个概念其实是更深刻的,它第一次出现. 如果声音是代表, 所以异味. 那么,空间.

Figure
图: 插图的感觉输入大脑的代表性的过程. 气味是化学成分和浓度水平我们的鼻子的感官的表示. 声音是由一个振动物体所产生的空气压力波的映射. 在望, 我们表示是空间, 并可能时间. 然而, 我们不知道它是什么的代表性.

我们可以对其进行检查并充分理解的声音,因为一个明显的事实 — 我们有一个更强大的感, 即我们的视线. 视线使我们能够理解听觉的感官信号,并把它们比作我们的感官体验. 实际上, 视线,使我们能够做出一个模型描述是什么声音.

为什么我们不知道后面的空间物理原因? 毕竟, 我们所知道的气味的经验背后的原因, 声音, 等. 究其原因,我们无法看到超越视觉的现实是感官的层次, 最佳地示出使用示例. 让我们考虑一个小规模的爆炸, 像鞭炮去关闭. 当我们经历这次爆炸, 我们将会看到闪光灯, 听到报告, 闻到了燃烧的化学品和感觉热, 如果我们足够接近.

这些经验的感受性都归结到同一个物理事件 — 爆炸, 其中的物理很好理解. 现在, 让我们,如果我们能骗过感官到具有相同的经历来看看, 在不存在真正的爆炸. 热和气味是相当容易重现. 也可以使用所产生的声音的经验, 例如, 一个高端家庭影院系统. 我们如何重建爆炸的视线的经验? 家庭影院的体验是一个再现真实的东西差.

至少在原则上, 我们能想到的未来场景,如在星际旅行的holideck, 当视线的经验可以重现. 但是,在该点处的视线也重新, is there a difference between the real experience of the explosion and the holideck simulation? The blurring of the sense of reality when the sight experience is simulated indicates that sight is our most powerful sense, and we have no access to causes beyond our visual reality.

Visual perception is the basis of our sense of reality. All other senses provide corroborating or complementing perceptions to the visual reality.

[This post has borrowed quite a bit from my book.]

轻旅行时间效应和宇宙学特点

This unpublished article is a sequel to my earlier paper (also posted here as “为无线电源和伽玛射线暴管腔围油栏?“). This blog version contains the abstract, introduction and conclusions. The full version of the article is available as a PDF file.

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Abstract

Light travel time effects (LTT) are an optical manifestation of the finite speed of light. They can also be considered perceptual constraints to the cognitive picture of space and time. Based on this interpretation of LTT effects, we recently presented a new hypothetical model for the temporal and spatial variation of the spectrum of Gamma Ray Bursts (GRB) and radio sources. In this article, we take the analysis further and show that LTT effects can provide a good framework to describe such cosmological features as the redshift observation of an expanding universe, and the cosmic microwave background radiation. The unification of these seemingly distinct phenomena at vastly different length and time scales, along with its conceptual simplicity, can be regarded as indicators of the curious usefulness of this framework, if not its validity.

Introduction

The finite speed of light plays an important part in how we perceive distance and speed. This fact should hardly come as a surprise because we do know that things are not as we see them. The sun that we see, 例如, is already eight minutes old by the time we see it. This delay is trivial; 如果我们想知道现在是怎么回事太阳, 所有我们需要做的就是等待八分钟. We, nonetheless, have to “正确” for this distortion in our perception due to the finite speed of light before we can trust what we see.

令人惊讶 (而很少强调) 是当涉及到​​敏感的议案, 我们不能后台计算看不到太阳,我们采取了拖延的方式相同. 如果我们看到一个天体运动以罢课高速, 我们无法弄清楚它是如何快速和方向 “真” 移动未做进一步的假设,. One way of handling this difficulty is to ascribe the distortions in our perception of motion to the fundamental properties of the arena of physics — 空间和时间. 另一个途径是接受我们的感知和底层之间的断线 “现实” 并处理它以某种方式.

Exploring the second option, we assume an underlying reality that gives rise to our perceived picture. We further model this underlying reality as obeying classical mechanics, and work out our perceived picture through the apparatus of perception. 换句话说, we do not attribute the manifestations of the finite speed of light to the properties of the underlying reality. 相反,, we work out our perceived picture that this model predicts and verify whether the properties we do observe can originate from this perceptual constraint.

空间, the objects in it, and their motion are, 大体上, the product of optical perception. One tends to take it for granted that perception arises from reality as one perceives it. In this article, we take the position that what we perceive is an incomplete or distorted picture of an underlying reality. Further, we are trying out classical mechanics for the the underlying reality (for which we use terms like absolute, noumenal or physical reality) that does cause our perception to see if it fits with our perceived picture (which we may refer to as sensed or phenomenal reality).

Note that we are not implying that the manifestations of perception are mere delusions. They are not; they are indeed part of our sensed reality because reality is an end result of perception. This insight may be behind Goethe’s famous statement, “错觉是光的真理。”

We applied this line of thinking to a physics problem recently. We looked at the spectral evolution of a GRB and found it to be remarkably similar to that in a sonic boom. Using this fact, we presented a model for GRB as our perception of a “luminal” boom, with the understanding that it is our perceived picture of reality that obeys Lorentz invariance and our model for the underlying reality (causing the perceived picture) may violate relativistic physics. The striking agreement between the model and the observed features, 然而,, extended beyond GRBs to symmetric radio sources, which can also be regarded as perceptual effects of hypothetical luminal booms.

In this article, we look at other implications of the model. We start with the similarities between the light travel time (LTT) effects and the coordinate transformation in Special Relativity (SR). These similarities are hardly surprising because SR is derived partly based on LTT effects. We then propose an interpretation of SR as a formalization of LTT effects and study a few observed cosmological phenomena in the light of this interpretation.

Similarities between Light Travel Time Effects and SR

Special relativity seeks a linear coordinate transformation between coordinate systems in motion with respect to each other. We can trace the origin of linearity to a hidden assumption on the nature of space and time built into SR, as stated by Einstein: “In the first place it is clear that the equations must be linear on account of the properties of homogeneity which we attribute to space and time.” Because of this assumption of linearity, the original derivation of the transformation equations ignores the asymmetry between approaching and receding objects. Both approaching and receding objects can be described by two coordinate systems that are always receding from each other. 例如, if a system K is moving with respect to another system k along the positive X axis of k, then an object at rest in K at a positive x is receding while another object at a negative x is approaching an observer at the origin of k.

The coordinate transformation in Einstein’s original paper is derived, in part, a manifestation of the light travel time (LTT) effects and the consequence of imposing the constancy of light speed in all inertial frames. This is most obvious in the first thought experiment, where observers moving with a rod find their clocks not synchronized due to the difference in light travel times along the length of the rod. 然而, in the current interpretation of SR, the coordinate transformation is considered a basic property of space and time.

One difficulty that arises from this interpretation of SR is that the definition of the relative velocity between the two inertial frames becomes ambiguous. If it is the velocity of the moving frame as measured by the observer, then the observed superluminal motion in radio jets starting from the core region becomes a violation of SR. If it is a velocity that we have to deduce by considering LT effects, then we have to employ the extra ad-hoc assumption that superluminality is forbidden. These difficulties suggest that it may be better to disentangle the light travel time effects from the rest of SR.

In this section, we will consider space and time as a part of the cognitive model created by the brain, and argue that special relativity applies to the cognitive model. The absolute reality (of which the SR-like space-time is our perception) does not have to obey the restrictions of SR. 特别是, objects are not restricted to subluminal speeds, but they may appear to us as though they are restricted to subluminal speeds in our perception of space and time. If we disentangle LTT effects from the rest of SR, we can understand a wide array of phenomena, as we shall see in this article.

Unlike SR, considerations based on LTT effects result in intrinsically different set of transformation laws for objects approaching an observer and those receding from him. More generally, the transformation depends on the angle between the velocity of the object and the observer’s line of sight. Since the transformation equations based on LTT effects treat approaching and receding objects asymmetrically, they provide a natural solution to the twin paradox, 例如.

Conclusions

Because space and time are a part of a reality created out of light inputs to our eyes, some of their properties are manifestations of LTT effects, especially on our perception of motion. The absolute, physical reality presumably generating the light inputs does not have to obey the properties we ascribe to our perceived space and time.

We showed that LTT effects are qualitatively identical to those of SR, noting that SR only considers frames of reference receding from each other. This similarity is not surprising because the coordinate transformation in SR is derived based partly on LTT effects, and partly on the assumption that light travels at the same speed with respect to all inertial frames. In treating it as a manifestation of LTT, we did not address the primary motivation of SR, which is a covariant formulation of Maxwell’s equations. It may be possible to disentangle the covariance of electrodynamics from the coordinate transformation, although it is not attempted in this article.

Unlike SR, LTT effects are asymmetric. This asymmetry provides a resolution to the twin paradox and an interpretation of the assumed causality violations associated with superluminality. 此外, the perception of superluminality is modulated by LTT effects, and explains gamma ray bursts and symmetric jets. As we showed in the article, perception of superluminal motion also holds an explanation for cosmological phenomena like the expansion of the universe and cosmic microwave background radiation. LTT effects should be considered as a fundamental constraint in our perception, and consequently in physics, rather than as a convenient explanation for isolated phenomena.

Given that our perception is filtered through LTT effects, we have to deconvolute them from our perceived reality in order to understand the nature of the absolute, physical reality. This deconvolution, 然而,, results in multiple solutions. 因此,, 绝对, physical reality is beyond our grasp, and any assumed properties of the absolute reality can only be validated through how well the resultant perceived reality agrees with our observations. In this article, we assumed that the underlying reality obeys our intuitively obvious classical mechanics and asked the question how such a reality would be perceived when filtered through light travel time effects. We demonstrated that this particular treatment could explain certain astrophysical and cosmological phenomena that we observe.

The coordinate transformation in SR can be viewed as a redefinition of space and time (或, more generally, 现实) in order to accommodate the distortions in our perception of motion due to light travel time effects. One may be tempted to argue that SR applies to the “实” 空间和时间, not our perception. This line of argument begs the question, what is real? Reality is only a cognitive model created in our brain starting from our sensory inputs, visual inputs being the most significant. Space itself is a part of this cognitive model. The properties of space are a mapping of the constraints of our perception.

The choice of accepting our perception as a true image of reality and redefining space and time as described in special relativity indeed amounts to a philosophical choice. The alternative presented in the article is inspired by the view in modern neuroscience that reality is a cognitive model in the brain based on our sensory inputs. Adopting this alternative reduces us to guessing the nature of the absolute reality and comparing its predicted projection to our real perception. It may simplify and elucidate some theories in physics and explain some puzzling phenomena in our universe. 然而, this option is yet another philosophical stance against the unknowable absolute reality.

为无线电源和伽玛射线暴管腔围油栏?

This article was published in the International Journal of Modern Physics D (IJMP–ð) 在 2007. It soon became the 最多访问文章 由杂志 一月 2008.

尽管它可能看起来像一个硬核物理的文章, 它实际上是哲学洞察力透过这个博客,我的书的申请.

This blog version contains the abstract, introduction and conclusions. The full version of the article is available as a PDF file.

Journal Reference: IJMP-D全. 16, 别. 6 (2007) PP. 983–1000.

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Abstract

The softening of the GRB afterglow bears remarkable similarities to the frequency evolution in a sonic boom. At the front end of the sonic boom cone, the frequency is infinite, much like a Gamma Ray Burst (GRB). Inside the cone, the frequency rapidly decreases to infrasonic ranges and the sound source appears at two places at the same time, mimicking the double-lobed radio sources. Although a “luminal” boom violates the Lorentz invariance and is therefore forbidden, it is tempting to work out the details and compare them with existing data. This temptation is further enhanced by the observed superluminality in the celestial objects associated with radio sources and some GRBs. In this article, we calculate the temporal and spatial variation of observed frequencies from a hypothetical luminal boom and show remarkable similarity between our calculations and current observations.

Introduction

A sonic boom is created when an object emitting sound passes through the medium faster than the speed of sound in that medium. As the object traverses the medium, the sound it emits creates a conical wavefront, 如图 1. The sound frequency at this wavefront is infinite because of the Doppler shift. The frequency behind the conical wavefront drops dramatically and soon reaches the infrasonic range. This frequency evolution is remarkably similar to afterglow evolution of a gamma ray burst (GRB).

Sonic Boom
图 1:. The frequency evolution of sound waves as a result of the Doppler effect in supersonic motion. The supersonic object S is moving along the arrow. The sound waves are “inverted” due to the motion, so that the waves emitted at two different points in the trajectory merge and reach the observer (at O) 同时. When the wavefront hits the observer, the frequency is infinity. After that, the frequency rapidly decreases.

Gamma Ray Bursts are very brief, but intense flashes of \gamma rays in the sky, lasting from a few milliseconds to several minutes, and are currently believed to emanate from cataclysmic stellar collapses. The short flashes (the prompt emissions) are followed by an afterglow of progressively softer energies. 因此,, the initial \gamma rays are promptly replaced by X-rays, light and even radio frequency waves. This softening of the spectrum has been known for quite some time, and was first described using a hypernova (fireball) model. In this model, a relativistically expanding fireball produces the \gamma emission, and the spectrum softens as the fireball cools down. The model calculates the energy released in the \gamma region as 10^ {53}10^ {54} ergs in a few seconds. This energy output is similar to about 1000 times the total energy released by the sun over its entire lifetime.

More recently, an inverse decay of the peak energy with varying time constant has been used to empirically fit the observed time evolution of the peak energy using a collapsar model. According to this model, GRBs are produced when the energy of highly relativistic flows in stellar collapses are dissipated, with the resulting radiation jets angled properly with respect to our line of sight. The collapsar model estimates a lower energy output because the energy release is not isotropic, but concentrated along the jets. 然而, the rate of the collapsar events has to be corrected for the fraction of the solid angle within which the radiation jets can appear as GRBs. GRBs are observed roughly at the rate of once a day. 因此,, the expected rate of the cataclysmic events powering the GRBs is of the order of 10^410^6 per day. Because of this inverse relationship between the rate and the estimated energy output, the total energy released per observed GRB remains the same.

If we think of a GRB as an effect similar to the sonic boom in supersonic motion, the assumed cataclysmic energy requirement becomes superfluous. Another feature of our perception of supersonic object is that we hear the sound source at two different location as the same time, 如图 2. This curious effect takes place because the sound waves emitted at two different points in the trajectory of the supersonic object reach the observer at the same instant in time. The end result of this effect is the perception of a symmetrically receding pair of sound sources, 哪, in the luminal world, is a good description of symmetric radio sources (Double Radio source Associated with Galactic Nucleus or DRAGN).

superluminality
图 2:. The object is flying from A through B at a constant supersonic speed. Imagine that the object emits sound during its travel. The sound emitted at the point (which is near the point of closest approach B) reaches the observer at O before the sound emitted earlier at . The instant when the sound at an earlier point reaches the observer, the sound emitted at a much later point A also reaches O. 所以, the sound emitted at A reaches the observer at the same time, giving the impression that the object is at these two points at the same time. 换句话说, the observer hears two objects moving away from rather than one real object.

Radio Sources are typically symmetric and seem associated with galactic cores, currently considered manifestations of space-time singularities or neutron stars. Different classes of such objects associated with Active Galactic Nuclei (AGN) were found in the last fifty years. 图 3 shows the radio galaxy Cygnus A, an example of such a radio source and one of the brightest radio objects. Many of its features are common to most extragalactic radio sources: the symmetric double lobes, an indication of a core, 喉喂食叶和热点的出现. 一些研究人员报告了更详细的运动学特性, 如热点的叶适当运动.

对称射电源 (银河系或河外星系) 和暴可能似乎是完全不同的现象. 然而, 其核心表现出类似的时间演化中的峰值能量, 但很大的不同时间常数. 伽玛射线暴的光谱迅速从进化 \gamma 区域的光,甚至射频余辉, similar to the spectral evolution of the hotspots of a radio source as they move from the core to the lobes. Other similarities have begun to attract attention in the recent years.

This article explores the similarities between a hypothetical “luminal” boom and these two astrophysical phenomena, although such a luminal boom is forbidden by the Lorentz invariance. Treating GRB as a manifestation of a hypothetical luminal boom results in a model that unifies these two phenomena and makes detailed predictions of their kinematics.

CygA
图 3:.The radio jet and lobes in the hyperluminous radio galaxy Cygnus A. The hotspots in the two lobes, the core region and the jets are clearly visible. (Reproduced from an image courtesy of NRAO/AUI.)

Conclusions

In this article, we looked at the spatio-temporal evolution of a supersonic object (both in its position and the sound frequency we hear). We showed that it closely resembles GRBs and DRAGNs if we were to extend the calculations to light, although a luminal boom would necessitate superluminal motion and is therefore forbidden.

This difficulty notwithstanding, we presented a unified model for Gamma Ray Bursts and jet like radio sources based on bulk superluminal motion. We showed that a single superluminal object flying across our field of vision would appear to us as the symmetric separation of two objects from a fixed core. Using this fact as the model for symmetric jets and GRBs, we explained their kinematic features quantitatively. 特别是, we showed that the angle of separation of the hotspots was parabolic in time, and the redshifts of the two hotspots were almost identical to each other. Even the fact that the spectra of the hotspots are in the radio frequency region is explained by assuming hyperluminal motion and the consequent redshift of the black body radiation of a typical star. The time evolution of the black body radiation of a superluminal object is completely consistent with the softening of the spectra observed in GRBs and radio sources. 此外, our model explains why there is significant blue shift at the core regions of radio sources, why radio sources seem to be associated with optical galaxies and why GRBs appear at random points with no advance indication of their impending appearance.

Although it does not address the energetics issues (the origin of superluminality), our model presents an intriguing option based on how we would perceive hypothetical superluminal motion. We presented a set of predictions and compared them to existing data from DRAGNs and GRBs. The features such as the blueness of the core, symmetry of the lobes, the transient \gamma and X-Ray bursts, the measured evolution of the spectra along the jet all find natural and simple explanations in this model as perceptual effects. Encouraged by this initial success, we may accept our model based on luminal boom as a working model for these astrophysical phenomena.

It has to be emphasized that perceptual effects can masquerade as apparent violations of traditional physics. An example of such an effect is the apparent superluminal motion, which was explained and anticipated within the context of the special theory of relativity even before it was actually observed. Although the observation of superluminal motion was the starting point behind the work presented in this article, it is by no means an indication of the validity of our model. The similarity between a sonic boom and a hypothetical luminal boom in spatio-temporal and spectral evolution is presented here as a curious, albeit probably unsound, foundation for our model.

One can, 然而,, argue that the special theory of relativity (SR) does not deal with superluminality and, 因此, superluminal motion and luminal booms are not inconsistent with SR. As evidenced by the opening statements of Einstein’s original paper, the primary motivation for SR is a covariant formulation of Maxwell’s equations, which requires a coordinate transformation derived based partly on light travel time (LTT) effects, and partly on the assumption that light travels at the same speed with respect to all inertial frames. Despite this dependence on LTT, the LTT effects are currently assumed to apply on a space-time that obeys SR. SR is a redefinition of space and time (或, more generally, 现实) in order to accommodate its two basic postulates. It may be that there is a deeper structure to space-time, of which SR is only our perception, filtered through the LTT effects. By treating them as an optical illusion to be applied on a space-time that obeys SR, we may be double counting them. We may avoid the double counting by disentangling the covariance of Maxwell’s equations from the coordinate transformations part of SR. Treating the LTT effects separately (without attributing their consequences to the basic nature of space and time), we can accommodate superluminality and obtain elegant explanations of the astrophysical phenomena described in this article. Our unified explanation for GRBs and symmetric radio sources, 因此, has implications as far reaching as our basic understanding of the nature of space and time.


照片由 NASA Goddard Photo and Video

虚幻宇宙 — Seeing Light in Science and Spirituality

我们知道,我们的宇宙是一个有点不真实. 星星,我们在夜空中看到, 例如, 是不是真的有. 他们可能已移动,甚至通过我们能看到他们的死亡时间. 这种延迟是由于需要为光从遥远的恒星和星系的时间到达我们. 我们知道这种延迟.

The same delay in seeing has a lesser known manifestation in the way we perceive moving objects. It distorts our perception such that something coming towards us would look as though it is coming in faster. Strange as it may sound, this effect has been observed in astrophysical studies. Some of the heavenly bodies do look as though they are moving several times the speed of light, while their “实” speed is probably a lot lower.

现在, 这种效应引发了一个有趣的问题–是什么 “实” speed? 如果眼见为实, the speed we see should be the real speed. 然后再, 我们知道光出行时间效应. So we should correct the speed we see before believing it. 那么是什么呢 “看” 意思? 当我们说我们看到的东西, 什么我们真正的意思?

Light in Physics

眼看涉及光, 显然. The finite speed of light influences and distorts the way we see things. This fact should hardly come as a surprise because we do know that things are not as we see them. The sun that we see is already eight minutes old by the time we see it. 这种延迟并不是什么大不了的事; 如果我们想知道现在是怎么回事太阳, 所有我们需要做的就是等待八分钟. We, nonetheless, have to “正确” 对于因光线的有限速度的扭曲,我们的看法,我们才可以相信我们所看到的.

令人惊讶 (而很少强调) 是当涉及到​​敏感的议案, 我们不能后台计算看不到太阳,我们采取了拖延的方式相同. 如果我们看到一个天体运动以罢课高速, 我们无法弄清楚它是如何快速和方向 “真” 移动未做进一步的假设,. 处理这种困难的一种方法是归于我们感知的扭曲物理学竞技场的基本性质 — 空间和时间. 另一个途径是接受我们的感知和底层之间的断线 “现实” 并处理它以某种方式.

Einstein chose the first route. In his groundbreaking paper over a hundred years ago, he introduced the special theory of relativity, in which he attributed the manifestations of the finite speed of light to the fundamental properties of space and time. One core idea in special relativity (SR) is that the notion of simultaneity needs to be redefined because it takes some time for light from an event at a distant place to reach us, and we become aware of the event. The concept of “现在” doesn’t make much sense, as we saw, when we speak of an event happening in the sun, 例如. 同时性是相对的.

Einstein defined simultaneity using the instants in time we detect the event. 检测, 他将其定义, involves a round-trip travel of light similar to Radar detection. We send out light, and look at the reflection. If the reflected light from two events reaches us at the same instant, they are simultaneous.
Another way of defining simultaneity is using sensing — we can call two events simultaneous if the light from them reaches us at the same instant. 换句话说, we can use the light generated by the objects under observation rather than sending light to them and looking at the reflection.

这种差异可能听起来像一个吹毛求疵的技术性, but it does make an enormous difference in the predictions we can make. 爱因斯坦的选择,导致有许多理想特性的数学图片, thereby making further development elegant.

The other possibility has an advantage when it comes to describing objects in motion because it corresponds better with how we measure them. We don’t use Radar to see the stars in motion; 我们仅仅感测的光 (或其他辐射) 他们来了. But this choice of using a sensory paradigm, rather than Radar-like detection, to describe the universe results in a slightly uglier mathematical picture.

在数学上的差异派生不同的哲学立场, 这反过来渗透到现实我们的物理图像的理解. 作为例证的, let us look at an example from astrophysics. Suppose we observe (通过射电望远镜, 例如) 在天空中的两个对象, roughly of the same shape and properties. The only thing we know for sure is that the radio waves from two different points in the sky reach the radio telescope at the same instant in time. We can guess that the waves started their journey quite a while ago.

For symmetric objects, if we assume (因为我们经常做的) 该波开始的旅程大致在同一时刻, we end up with a picture of two “实” 对称的叶片或多或少的方式看到它们.

But there is different possibility that the waves originated from the same object (这是在运动) 在两个时间不同的时刻, 在同一时刻到达望远镜. This possibility explains some spectral and temporal properties of such symmetric radio sources, which is what I mathematically described in a recent physics article. 现在, which of these two pictures should we take as real? 两个对称的物体,因为我们看到他们或一个物体以这样的方式移动,就好像给我们的印象? Does it really matter which one is “实”? Does “实” 意味着在这方面的任何?

The philosophical stance in implied in special relativity answers this question unequivocally. There is an unambiguous physical reality from which we get the two symmetric radio sources, although it takes a bit of mathematical work to get to it. 数学排除了移动以这样的方式单一对象的可能性,以模拟的两个对象. 从本质, 我们看到的是什么就在那里.

另一方面, if we define simultaneity using concurrent arrival of light, we will be forced to admit the exact opposite. What we see is pretty far from what is out there. We will confess that we cannot unambiguously decouple the distortions due to the constraints in perception (the finite speed of light being the constraint of interest here) from what we see. There are multiple physical realities that can result in the same perceptual picture. The only philosophical stance that makes sense is the one that disconnects the sensed reality and the causes behind what is being sensed.

这种脱节的情况并不少见思想的哲学流派. 现象学, 例如, 认为,空间和时间是不客观的现实. 他们只是我们的感知中. 所有这一切发生在时间和空间的现象仅仅是捆绑了我们的看法. 换句话说, 空间和时间是从知觉所产生的认知结构. 因此,, 所有我们所归诸于空间和时间的物理特性只适用于以惊人的现实 (当我们感觉到它的现实). 本体的现实 (持有我们的感知的物理原因), 相比之下, 仍超出了我们的认知范围.

The ramifications of the two different philosophical stances described above are tremendous. Since modern physics seems to embrace a non-phenomenalistic view of space and time, 它发现自己不符合哲学的一个分支,. 哲学和物理学之间的鸿沟已经发展到这种程度,诺贝尔得奖物理学家, 史蒂芬温伯格, 想知道 (在他的书 “终极理论之梦”) 为什么从哲学到物理学的贡献一直这么小得惊人. 这也提示哲学家做出类似声明, “无论是“本体的现实导致惊人的现实’ 还是“本体的现实是独立于我们的感知它’ 还是“我们感觉到现实的本体,’ 问题仍然是本体现实的概念,是一个完全冗余的概念,科学的分析。”

一, 几乎是偶然, 很难重新定义为光的空间和时间属性的有限速度的影响是,我们明白任何影响被迅速转移到光幻想的境界. 例如, 在看到太阳的八分钟的延迟, because we readily understand it and disassociate from our perception using simple arithmetic, 被认为是单纯的错觉. 然而, 在我们的观念中快速移动的物体扭曲, 尽管源自同一源被认为是空间和时间的属性,因为它们是更复杂.

We have to come to terms with the fact that when it comes to seeing the universe, 有没有这样的事,作为一个错觉, 这也许正是歌德指出,当他说, “错觉是光的真理。”

的区别 (或缺乏) 光学幻觉和真实之间,在哲学最古老的话题之一. 毕竟, 它是关于知识与现实之间的区别. 知识被认为是我们认为对的东西,, 在现实中, 是 “其实并非如此。” 换句话说, 知识是一种体现, 或外部的东西精神的形象, 如下面的图中.
Commonsense view of reality
在这张照片, 黑色箭头表示创造知识的过程, 其中包括感知, 认知活动, 并实行纯粹理性. 这是图片物理学已经接受.
Alternate view of reality
虽然承认了我们的看法可能是不完美的, 物理学假设,我们可以打通越来越精细的实验密切的外部现实, 和, 更重要的是, 通过更好的理论化. 相对论的特殊和一般的理论是这一观点的现实的辉煌应用例子,简单的物理原理是使用纯粹理性强大的机器的逻辑必然的结论,不懈地追求.

但还有另一种, 知识与现实的另一种观点认为已经存在了很长一段时间. 这是关于感知的现实,我们的感官输入的内部认知表示看法, 如下图所示.

在此视图中, 知识和感知的现实是内部认知结构, 虽然我们都来把它们作为单独的. 什么是外部并不现实,因为我们认为它, 但一个不可知的实体后面感觉输入的物理原因引起. 在图示的例子, 第一个箭头表示的感测的过程, 和第二箭头表示认知和逻辑推理步骤. 为了应用这一观点的现实和知识, 大家纷纷猜测绝对现实的本质, 不可知的,因为它是. 一个可能的候选人绝对现实是牛顿力学, 这给出了一个合理的预测为我们感知的现实.

总结, 当我们试图处理由于认知的扭曲, 我们有两个选择, 两个可能的哲学立场. 一种是接受的失真作为我们的空间和时间的一部分, as SR does. The other option is to assume that there is a “更高” 实际上从我们检测到的现实截然不同, 其属性,我们只能猜想. 换句话说, 一种选择是住在一起的失真, 而另一种是提出​​的猜测为更高的现实. Neither of these options is particularly attractive. 但猜测路径是相似的接受现象论的观点. 这也导致自然如何现实认知神经科学观察, 它研究的认知背后的生物学机制.

In my view, the two options are not inherently distinct. The philosophical stance of SR can be thought of as coming from a deep understanding that space is merely a phenomenal construct. If the sense modality introduces distortions in the phenomenal picture, we may argue that one sensible way of handling it is to redefine the properties of the phenomenal reality.

Role of Light in Our Reality

从认知神经科学的角度, 我们看到的一切, 感, 感受和思考,是我们大脑中的神经元相互联系和微小的电信号在他们的结果. 这种观点一定是正确的. 还有什么? 我们所有的思念与牵挂, 知识和信仰, 自我与现实, 生死 — 一切都在一个仅仅纹状体神经元半公斤糊糊, 我们称我们的大脑的灰色物质. 有没有别的. 无!

事实上, 这种观点实际上在神经科学的现象主义的确切回音, 它认为一切都感觉或心理构造的包. 空间和时间也认知结构在我们的大脑, 和其他事物一样. 他们是精神的图片我们的大脑编造出来的,我们的感官接收感觉输入. 从我们的感官知觉产生,我们的认知过程制造, 时空连续体是物理学的舞台. 我们所有的感官, 眼前是目前占主导地位. 感官输入映入眼帘的是光. 在由大脑创造出来的光落在我们的视网膜空间 (或在哈勃望远镜的光传感器), 这是一个惊喜,没有什么能比光速?

这个哲学立场是我的书的基础, 虚幻宇宙, 它探讨了共同的线索结合物理学和哲学. 这样的哲学沉思通常会得到来自美国物理学家一个坏名声. 物理学家, 哲学是一个完全不同的领域, 知识的另一种筒仓. 我们需要改变这个信念,欣赏不同的知识孤岛之间的重叠. It is in this overlap that we can expect to find breakthroughs in human thought.

This philosophical grand-standing may sound presumptuous and the veiled self-admonition of physicists understandably unwelcome; but I am holding a trump card. Based on this philosophical stance, I have come up with a radically new model for two astrophysical phenomena, and published it in an article titled, “为无线电源和伽玛射线暴管腔围油栏?” in the well-known International Journal of Modern Physics D in June 2007. This article, which soon became one of the top accessed articles of the journal by Jan 2008, is a direct application of the view that the finite speed of light distorts the way we perceive motion. Because of these distortions, the way we see things is a far cry from the way they are.

We may be tempted to think that we can escape such perceptual constraints by using technological extensions to our senses such as radio telescopes, electron microscopes or spectroscopic speed measurements. 毕竟, these instruments do not have “感悟” per se and should be immune to the human weaknesses we suffer from. But these soulless instruments also measure our universe using information carriers limited to the speed of light. We, 因此, cannot escape the basic constraints of our perception even when we use modern instruments. 换句话说, the Hubble telescope may see a billion light years farther than our naked eyes, but what it sees is still a billion years older than what our eyes see.

Our reality, whether technologically enhanced or built upon direct sensory inputs, is the end result of our perceptual process. To the extent that our long range perception is based on light (and is therefore limited to its speed), we get only a distorted picture of the universe.

Light in Philosophy and Spirituality

扭曲光线和现实的故事是,我们似乎已经知道这一切很长一段时间. Classical philosophical schools seem to have thought along lines very similar to Einstein’s thought experiment.

Once we appreciate the special place accorded to light in modern science, we have to ask ourselves how different our universe would have been in the absence of light. 当然, light is only a label we attach to a sensory experience. 因此,, to be more accurate, we have to ask a different question: if we did not have any senses that responded to what we call light, would that affect the form of the universe?

The immediate answer from any normal (就是说, non-philosophical) person is that it is obvious. If everybody is blind, everybody is blind. But the existence of the universe is independent of whether we can see it or not. Is it though? What does it mean to say the universe exists if we cannot sense it? Ah… the age-old conundrum of the falling tree in a deserted forest. Remember, the universe is a cognitive construct or a mental representation of the light input to our eyes. It is not “out there,” but in the neurons of our brain, as everything else is. In the absence of light in our eyes, there is no input to be represented, ergo no universe.

If we had sensed the universe using modalities that operated at other speeds (echolocation, 例如), it is those speeds that would have figured in the fundamental properties of space and time. This is the inescapable conclusion from phenomenalism.

光在创造我们的现实,还是宇宙中的角色是西方宗教思想的心脏. 宇宙缺乏光线的不只是您已经关掉了灯的世界. 这的确是一个宇宙缺乏自身, 一个不存在的宇宙. 正是在这种背景下,我们必须明白的声明背后的智慧 “该地是, 和无效的” 直到神使光线是, 说 “要有光。”

可兰经也说, “真主是天地之光,” 这是反映在古印度的著作之一: “从黑暗走向光明带领我, 从虚幻到真实带领我。” 光从虚幻的虚空把我们的角色 (虚无) 以现实确实理解了很长, 很久. 难道古代的圣人和先知知道的事情,我们现在才开始发现我们所有的知识应该进步?

我知道我可能会急于在天使不敢涉足, 对于重新诠释经文是一个危险的游戏. Such foreign interpretations are seldom welcome in the theological circles. 不过,我投靠的是,我要找同意灵性哲学的形而上学的观点, without diminishing their mystical or theological value.

The parallels between the noumenal-phenomenal distinction in phenomenalism and the Brahman-Maya distinction in Advaita are hard to ignore. This time-tested wisdom on the nature of reality from the repertoire of spirituality is now reinvented in modern neuroscience, 它把现实,由大脑产生一种认知表征. 大脑使用感觉输入, 内存, 意识, 甚至语言成分在炮制我们的​​现实感. 这种观点的现实, 然而,, 是物理的东西是没有来的条款. 但是在某种程度上,它的舞台 (空间和时间) 是现实的一部分, 物理学是不能幸免的哲学.

由于我们的知识的界限推向越走越, 我们开始发现人类努力的不同分支之间迄今没有料​​到,常常令人惊讶的互连. 在最后的分析, 怎么能对我们知识的不同领域是相互独立的,当我们所有的知识存在于我们的大脑? 知识是我们的经验认知表征. 但随后, 这样的现实; 这是我们的感官投入认知表征. 这是一个谬论认为知识是一个外部的现实我们的内部表示, 因此,与此不同的. 知识和现实是内部认知结构, 虽然我们都来把它们作为单独的.

Recognizing and making use of the interconnections among the different domains of human endeavour may be the catalyst for the next breakthrough in our collective wisdom that we have been waiting for.