Content Listing

Summary

In Chapter 1 it was proposed that we are living through an Electronic Renaissance, with the global acceptance of modern communications, increased data storage and transfer capacities enabling interaction on an unprecedented level. It’s not just big business and governments with this communications capacity; individuals have been quick to take up computer use and now use the basic mobile phone as a mass communication instrument. Each incremental advance follows principles of endogenous order. Out of the chaos of vast technological capacity, entrepreneurial players and a willing and eager global market comes an embracement of media for social and entertainment purposes by a substantial proportion of the world’s population.

Social media gives individuals, as well as large and small businesses, a direct way to interact, and to have access to and promote products and services. Businesses using social media channels such as Facebook, Twitter, LinkedIn and YouTube have a responsibility to ensure that content on their pages is accurate and legally compliant, irrespective of who put it there.

Social media has become the next stage of communications, bypassing post and telephone and becoming truly international. Social media may be briefl y defined as online networking facilitating social interaction amongst individuals.

More broadly, social media refers to the numerous online applications which permit the creation and exchange of personal information such as text, photos and videos. Social media differs from standard forms of media, such as newspapers, television and radio. Social media facilitates mass individual communications to the global community. As a corollary, social media is community-based for individuals, allowing communications around particular interests, personal content sharing, collaborations, networking and exposure.

Summary

Because of the very architecture of personal space in the offline world, social interactions used to be relatively private. The retelling of anecdotes and questionable behaviour in a social environment would, until the last decade or two, be taken with a grain of salt and with some expectation of embellishment or exaggeration. Rarely would an employer or others be faced with hard evidence, such as photographs, statements of admission by the employee or digital logs. Today, however, social media allows, if not encourages, such actions. In the words of the NSW Industrial Relations Commissioner, there exists:

greater risk of private exchanges over the Internet becoming public than was ever the case with private spoken conversations. Exchanges over ‘Facebook’ and other social media appear to have an increasing likelihood of surfacing publicly at some later time.

And of a Fair Work Australia Commissioner:

What might previously have been a grumble about their employer over a coffee or drinks with friends has turned into a posting on a website that, in some cases, may be seen by an unlimited number of people. Posting comments about an employer on a website (Facebook) that can be seen by an uncontrollable number of people is no longer a private matter but a public comment.

It is well accepted that behaviour outside working hours may have an impact on employment.

The underlying relationship in the workplace between the employer and employee has not changed, but the use and misuse of social media facilitates the free flow of information to a wider audience, potentially harming the interests of the employer (and, indeed, of the employee). A ban on the use of such devices might be a sledgehammer reaction, and in many businesses would be impossible, particularly where social interaction is encouraged for the benefit of the business. Restricting use after hours has its own problems. In Stutsel v Linfox Australia Pty Ltd the Commissioner commented that Facebook communication was of the nature ‘of a group of friends letting off steam and trying to outdo one another in being outrageous … [and] has much of the favour (sic) of a conversation in a pub or cafe, although conducted in an electronic format’.

Summary

The systemisation of laws and societies’ penchant for structure and order reflect the endogenous nature of humanity’s development. Each culture develops a principle-based rule set to administer justice. The more complex the society, the richer the system. Rules of evidence are one subset of these developments which provide collective certainty, predictability and justice. Many of these principles have evolved over eons, and now are put the test by changes wrought by the emergence and development of technology. The regulations depend upon the perspective of the players who fashion, mostly unconsciously, community norms. Societies’ ‘norms and institutions’ are necessary for a functioning society; the ‘more complex’ the society the greater the structure; however, state action can ‘undermine or destroy these norms and institutions, with potentially catastrophic effect’.

It is said that a verbal contract is worth the paper it is written on. Although the common law recognises oral contracts, this oxymoron reflects the problems associated with proving not only the terms of a verbal contract, but also its very existence. The law of evidence is central to legal systems. Its restraints, rules and procedures aim to provide certainty and reliability within the criminal and civil justice systems. New and unanticipated problems have emerged when these historic and sometimes antiquated rules of evidence have been applied to electronic documents and records.

Summary

The Australian Communications and Media Authority (ACMA) is responsible for administering legislation regarding the content and regulation of most forms of electronic communications. This chapter deals with the role of ACMA and the regulation of internet, television and radio communications.

The Australian Communications and Media Authority

ACMA is responsible for the regulation of broadcasting, radio communications, telecommunications and online content. Its responsibilities include:

Summary

A major accomplishment of Einstein's Theory of Special Relativity (SR) was the demonstration that the laws of physics took the same form for all inertial observers. In more relevant language we would say that the laws of physics were independent of the reference frame and coordinate system chosen for their expression – but only for inertial reference frames or, what is equivalent, for coordinate systems related by Lorentz transforms. This covariance of inertial coordinate systems allowed Einstein to write the laws of mechanics and of electrodynamics in ways that revealed new aspects (e.g., E = mc2) and extended their validity to reference frames moving at high velocity.

It was thus a principal purpose of General Relativity (GR) to extend this Principle of General Covariance – that the equations of physics were invariant to change of coordinate systems – to all reference frames, including accelerating ones. Needed for this purpose are tools of mathematical physics that preserve equalities under all changes of coordinate systems and thus – as Einstein would put it – free physics from the tyranny of coordinates. The required tools were providentially at hand in the form of the Absolute Differential Calculus, a coordinate-independent version of calculus being developed by (mostly Italian) mathematicians. Among the tools in that development were mathematical quantities associated with geometry that all transformed in the same manner under changes in coordinate systems, so that equalities in any coordinate system led to equalities in all. These were tensors, different forms for which have since been employed in many areas of advanced physics.

The idea of tensors is simple enough: if tensors A and B are equal in coordinate system S, and transform to A′ and B′ in system S′, then it follows that A′ = B′ there also. The trick is to find tensors to represent physical quantities of interest; fortunately for GR, in which geometrically related objects play a central role, tensor representations exist for most applications.

The remainder of this chapter is devoted to an explanation of the most basic properties of tensors and of their manipulations in the service of the differential geometry employed in GR. Tensor analysis is not really difficult, but it is different from the mathematics to which students have normally been exposed and so requires one's attention in order to understand.

Summary

Prior to digital storage and the internet, the nature and architecture of the storage of information made access difficult and copying relatively arduous and time consuming. In the 21st century, information of all types is created, shared and, significantly, reproduced digitally. Material placed online is subject to unrestricted reproduction. The demand for all forms of information is a vast opportunity for order and structure – and for exploitation. The sheer number of users, and their voracious appetites, leads to increased supply. This is demonstrated by the vast number of websites which have emerged to reproduce material subject to copyright, and the almost complete disregard for the law by individual users.

The internet facilitates the swift reproducing and exchange of digital material. Hyperlinking and framing can offer new possibilities for infringement of copyright. Works protected by copyright, such as music and videos, can be easily transferred in peer-to-peer dealings. Such transfers have become the target of copyright owners. This chapter explores these issues and developments and the relationship between copyright and electronic commerce. It is not intended to state the law relating to copyright, other than via a brief overview. The advent of electronic commerce and the internet have necessitated a rethink of intellectual property issues by the World Intellectual Property Organization (WIPO), the courts and the legislature. The proliferation of material on the internet – written, aural and graphic – has posed new questions and resulted in the creation of new rights internationally.

Summary

Social media permits people to engage in social discourse with hundreds of friends and associates. Online, everyone is a publisher. People use handheld devices to communicate to individuals, small and large groups and the world at large at any time – while waiting in queues, on public transport, whilst walking and indeed whilst driving. One modern danger is that users are not circumspect when texting off-the-cuff remarks or tweeting immediate and spontaneous responses. Each day users send 250 billion emails and make 600 million contributions to Twitter. Defamation is a real issue because of the audience which can access such discourses. When written, rather than spoken, words take on a sterner and more deliberate meaning than may have been intended, and injudicious replies may be sent in the heat of the moment.

From the beginning, the boundaries of appropriate and acceptable behaviour on the internet have been challenged. The notion that the internet is the last bastion of free speech has produced a general mindset that the laws that bind and regulate social behaviour should not apply in cyberspace. There has developed a sense that anything written in a digital forum should somehow be immune from oversight and censure. Courts internationally have disagreed with this view and have applied defamation laws to social media.

Summary

The pace of change in cosmology has accelerated remarkably in the years bracketing the turn of the twenty-first century, so that many of the classical texts are becoming dated. The purpose of this text is to provide a coherent description of current theory underlying modern cosmology, at a level appropriate for advanced undergraduate students. To do so, the book is loosely organized around two pedagogical principles.

First, while the development of physical cosmology is heavily mathematical, the book emphasizes physical concepts over mathematical results wherever possible. The mathematics of General Relativity and of relativistic cosmology are beautiful, elegant, and seductive. It is a real temptation to develop theoretical cosmology as a purely mathematical structure, much as can be done with classical thermodynamics. But to do so is to lose sight of the deeper meaning of cosmology and to leave the student unprepared for the changes in the field that are almost certainly coming. In Einstein's inimitable phrasing, “Mathematics is all very well, but Nature leads us by the nose.” The book endeavors to lead the student gently, if not always easily, toward a useful understanding of the physical underpinnings of modern cosmology.

Cosmology is an inherently uncertain science, because of both the remoteness (spatial and temporal) of its subjects and the incompleteness of its observational foundations. It is thus not surprising that recent technological advances in observational astronomy have produced something of a revolution in cosmological theory, from inflation to dark energy to new theories of galaxy origins. But interpretations of cosmological observations are typically based on conceptual models and (in some cases) underlying physics of uncertain validity, so wherever possible the book derives and interprets its results in a manner conducive to re-interpretation when new observations and/or physics so permit. The book is also at some pains to point out the uncertainties of cosmology theory arising from incomplete observational evidence and adoption of specific physical models. Modern cosmology is truly an intellectual wonder, but is likely to experience considerable revision as new observations and physics come to bear upon it. This book will, hopefully, prepare students for such changes.

Summary

Information in cyberspace is eternal. The very architecture of cyberspace facilitates information flow, the antithesis of privacy. Digital files reproduce faithfully, permitting an avalanche of material to be viewed, shared and stored. Social media allows millions to share thoughts, images and videos of brilliant quality and (sometimes) questionable taste. Never has information been so available at our fingertips. The expression ‘going viral’ has entered the vocabulary to describe this phenomenon. It is insidious. It is glorious. In any event it encroaches at a galloping pace on many individuals’ privacy.

‘Privacy’ has numerous meanings, and its importance varies greatly among individuals, communities, organisations and governments. It is an aspect of freedom and human rights. Civil libertarians may believe that our actions and behaviour should not be subject to public or governmental scrutiny; protectionists may accept such erosions for the greater good in the name of law and order.

Historically, governments seem to have pursued increasing and systemic invasions of privacy in the name of law and order, fighting crime and terrorism. However, their role is in fact to ensure and balance security issues and the proper protection of the privacy rights of the individual. In the 1990s the Clipper Chip was proposed by the US Government, ostensibly for the purpose of allowing the government to override individual encryption to protect society from ‘gangsters, terrorists and drug users’. Such a process would have allowed the government to access and decipher all encrypted files. The proposal was unsuccessful. In Australia in 1984, an attempt to pass a Privacy Act failed because it set in place an anti-privacy provision: a central national identification card.

Summary

Cosmology, as the term is currently used, is the study of the structure, contents, and evolution of the Universe on the largest scales. Relativistic cosmological models characterizing the evolution of the Universe on such scales are quantitative forms for the metric tensor components as derived from the Einstein Field Equations. In many cases these are superficially similar to the Newtonian forms of Chapter 1, but they differ from Newtonian models in conceptual interpretations and in several key details. In particular, relativistic cosmological models incorporate all forms of gravitating energy and matter, not just ordinary matter alone; and the character of the models reflects the curvature of space-time in place of Newtonian total energy.

Cosmological coordinates

The field equations are so complex that their practical solution requires the adoption of a coordinate system fully expressing the symmetries of the application. In cosmology, those symmetries usually arise from the Cosmological Principle: on sufficiently large scales the Universe is homogeneous and isotropic, the same everywhere and in all directions (at any given time). The system of galaxies in an expanding, spatially uniform Universe may then be thought of as one in which the galaxies are all falling upward in a uniform gravitational field. This suggests adoption of an appropriately symmetric coordinate system falling with the galaxies, which (by the Equivalence Principle) effectively defines an inertial reference frame, inside which the galaxies are not moving with respect to each other and the physics of SR are valid. Such a coordinate system – which may usefully be visualized as an expanding grid that carries galaxies with it as it expands – is commonly called a co-moving coordinate system. Adoption of such a system further suggests the validity of a universal time system, one that applies to all galaxies and that greatly simplifies the physics of universal expansion.

The choice of coordinate system leads to expressions for the metric tensor components in terms of the coordinates. In such a co-moving system the coordinates of a grid point (i.e., galaxy) do not change as a consequence of the expansion of the Universe; the only time-varying element is the Expansion Function a(t), which, as in Newtonian cosmology, is non-dimensional and normalized so that a(t0)= 1.

Summary

From a cosmological perspective, matter is the energy component with negligible EOS parameter so that its energy density varies with expansion as εm ∝ a−3. Unlike the case with radiation, matter in the Universe comes in many forms and is only partially visible or otherwise detectable, so its gravitating density is difficult to evaluate.

The current standard model of particle physics includes two main types of fermion, hadrons and leptons. Hadrons are quark composites and are the only particles subject to the strong nuclear force. They are further divided into two types. Baryons are three-quark composites: the only stable baryons are protons and neutrons, so that atomic nuclei are made up entirely of baryons, and protons/ neutrons are thus often called nucleons. Mesons are two-quark composites and are all unstable on short time scales, so that the only stable hadrons are the nucleons. Leptons are subject to electroweak forces but not to the strong nuclear force; stable leptons are the electron and its anti-particle the positron, and neutrinos. For convenience – and since the Universe is overall electrically neutral – electrons are often included with nucleons as ‘baryonic matter’.

Baryonic matter is what is usually meant by ‘normal matter’– it is the stuff we, and all we can see around us, are made of. But our ability to detect fundamental particles is limited to masses less than those achievable by current particle accelerators, which (with the advent of the Large Hadron Collider) are limited to masses on the order of a few times 100 GeV or less (nucleons have masses of a bit less than 1 GeV). Since some exotic particle theories predict particles of even greater mass, there is probably a lot left to discover in the realms of possible forms of matter.

So it really should be of no great surprise to find cosmological evidence for currently unknown forms of matter. The gravitational evidence for ‘dark matter’ has been growing for at least 80 years, and has reached the point of near certainty. This exotic stuff appears to have no appreciable cross-section to electromagnetism so that it neither absorbs nor emits detectable radiation: hence, ‘dark’. It can only be detected and measured in terms of the influence of its gravitation on ordinary matter and light.

Summary

When a radically new situation is presented to the law it is sometimes necessary to think outside the square … this involves a reflection upon the features of the Internet that are said to require a new and distinctive legal approach.

Cyberspace is an illusion. There is no such place. Many terrestrial norms do not and cannot apply to such a fictitious construct. Nevertheless, cyberspace users perceive metaphorical chat rooms, folders, files, shops, libraries and so forth. They live digital lives with digital personas in ‘places’ such as Second Life, Twitter and Facebook. The reality is that each step of the digital experience is rooted terrestrially. Traditional legal principles are applicable to the majority of electronic commerce disputes. Nevertheless, the operation of electronic commerce in cyberspace results in new circumstances to which legal jurists cannot readily apply established legal rules.

The borderless nature of the internet often hides or disguises the origin of particular websites and corresponding information. Questions sometimes arise as to the country or state whose courts have jurisdiction to adjudicate on a matter, and as to which law is to be applied. Courts also have to determine issues such as where conduct occurs – at the computer, the server, the place of business or residence or somewhere else? – and thus which time zone applies. This area of law is referred to as conflict of laws or private international law, and its principles are well established.

Summary

The Concordance Cosmological Model (CCM), aka the Standard Model of Big Bang Cosmology, is the solution to the Friedmann Equations that incorporates parameters that represent best estimates taken from a wide range of observations, and that purports to explain not only observations of universal expansion but also consequences of primordial cosmology and of structure formation in the Universe. Perhaps somewhat surprisingly, all these matters can be successfully modelled with one set of parameters for the Friedmann Equations; hence ‘Concordance’. The parameters of the CCM are the following.

Curvature From several indirect lines of evidence, the Universe appears to be geometrically flat or nearly so: Ω0 ≈ 1. The principal reason for this choice is the apparent need for a nearly flat geometry in order to account for the Hubble Relation for SN Ia supernovae (Section 15.2), and for the shape of the CMB anisotropy spectrum (Chapter 17). A (very nearly) flat geometry is also a robust prediction of inflation (Chapter 16).

Radiation energy density The well-observed CMB temperature, together with expected primordial neutrinos, implies εr, 0 = 7.01 × 10−14 J/m3.

Matter density Gravitational evidence (Chapter 12) and model fitting to diagnostics (Chapter 14) point to ρm, 0 ≈ 2.6 × 10−27 kg/m3 (corresponding to εm, 0 ≈ 2.4 × 10−10 J/m3), of which ∼ 15% is baryonic (as inferred from primordial nucleosynthesis, Section 16.3); and the remaining exotic dark matter. These densities are also consistent with details in the CMB anisotropy spectrum (Section 17.3).

Dark energy An energy component arising from the cosmological constant of εΛ,0 ≈ 6.4×10−10 J/m3 is apparently needed to (1) fit the SN Ia brightnesses to a plausible Hubble Relation, (2) provide enough energy to flatten the Universe, and (3) yield an expansion model in which the Universe is at least as old as the oldest stars in our Galaxy. The nature and density of this energy is uncertain; see Chapter 13.

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8 - Cosmological Field Equations

16 - Particle Era

3 - Social media law

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6 - Social media and the workplace

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19 - Evidence of electronic records

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10 - Censorship online

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4 - General covariance

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14 - Copyright issues in electronic commerce

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II - General Relativity

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7 - Defamation in cyberspace

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Contents

Preface

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Dedication

8 - Privacy in cyberspace

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13 - Dark energy

3 - Relativistic cosmology

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12 - Matter

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17 - Jurisdiction in cyberspace

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15 - Concordance Cosmological Model

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