Deciphering Modern Cosmology: Energy in the Universe

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Deciphering Modern Cosmology: Energy in the Universe Deciphering Modern Cosmology: Energy in the Universe A. Macleod [email protected] Abstract. The problem of energy conservation in the universe is inves- tigated both in the context of conventional cosmology and alternatives. Table of Contents Deciphering Modern Cosmology: Energy in the Universe ::::::::::::::: 1 Overview........................................................5 The Societal Energy Problem....................................5 What can Science Do?..........................................6 Energy and Science............................................7 Energy in the Universe.........................................9 An Evaluation of Consensus Cosmology........................... 10 1 An Interpretation of Modified Newtonian Dynamics................ 12 1.1 Introduction.............................................. 12 1.2 Varying Gravity........................................... 13 1.3 Joining the Flow.......................................... 16 1.4 Continuous Outflow....................................... 20 1.5 Peculiar Velocity.......................................... 21 1.6 Discussion................................................ 23 2 Cosmology: An Operational Approach............................ 25 2.1 Introduction.............................................. 25 2.2 The Energy Problem....................................... 26 2.3 The Luminosity Distance in Special Relativity................ 27 2.4 Peculiar Velocity.......................................... 31 2.5 Additional Factors......................................... 35 2.6 Discussion................................................ 36 3 Acceleration and Special Relativity............................... 38 3.1 Introduction.............................................. 38 3.2 The Twin Paradox......................................... 40 3.3 Gravitational Energy...................................... 42 3.4 Mach’s Principle.......................................... 45 3.5 Conclusion............................................... 46 4 Can G Vary?.................................................. 49 4.1 Introduction.............................................. 49 4.2 The Model............................................... 50 4.3 A Comparison with MOND................................. 54 4.4 Peculiar Velocity.......................................... 55 4.5 Discussion................................................ 60 Constant Expansion....................................... 60 Space-Time............................................... 61 4.6 Conclusion............................................... 63 5 A Universe Stretching at Light Speed............................. 66 5.1 Introduction.............................................. 66 5.2 Historical Background..................................... 66 5.3 Updating the Milne Model.................................. 67 3 5.4 The Luminosity Distance - Redshift Relation................. 68 5.5 The Luminosity of the Cosmic Microwave Background Radiation 70 5.6 Energy Loss by Cosmological Photons....................... 73 5.7 Discussion................................................ 75 6 The Local Expansion in a Coasting Universe...................... 78 6.1 Introduction.............................................. 78 6.2 The Expansion in the Absence of Gravity.................... 78 6.3 Central Gravitational Force................................. 81 6.4 Cosmological Considerations................................ 82 6.5 The Expansion in Standard Cosmology....................... 84 7 The Expanding Balloon Analogy in Cosmology.................... 87 7.1 Introduction.............................................. 87 7.2 The Balloon Analogy...................................... 89 7.3 Fixing the Universe........................................ 91 7.4 Cosmology without a Model................................ 93 7.5 The Energy Problem....................................... 94 7.6 Conclusion............................................... 97 8 Is Potential Energy Real?....................................... 105 8.1 Introduction.............................................. 105 8.2 Quantifying Potential Energy............................... 106 8.3 At the Limits............................................. 108 8.4 The Role of Forces........................................ 110 8.5 Conclusion............................................... 113 9 The Influence of Future Absorbers on Photon Emission............. 114 9.1 Introduction.............................................. 114 9.2 Cosmic Experiments....................................... 115 9.3 Non-Local Effects in Quantum Theory....................... 117 9.4 The Zero-Point Energy..................................... 120 9.5 Forces................................................... 122 9.6 Discussion................................................ 123 9.7 Conclusion............................................... 125 10 A DIY Theory of Everything.................................... 128 10.1 Introduction.............................................. 128 10.2 The Problem............................................. 129 The Rules................................................ 130 What the Experts Say..................................... 131 10.3 A New Approach?......................................... 133 The Future............................................... 133 Cranks and Mavericks..................................... 134 Religion.................................................. 136 An Interdisciplinary Approach.............................. 136 The Contribution of the Machine............................ 137 10.4 The Role of the Amateur................................... 138 Conservation of Energy.................................... 139 An Energy Audit of the Universe............................ 140 4 Free Energy.............................................. 141 Time Travel.............................................. 141 Quantum Theory.......................................... 142 Randomness.............................................. 143 Do we Really Understand Forces?........................... 144 Action at a Distance....................................... 145 Infinity................................................... 146 The Idea................................................. 147 10.5 Sharing the New Idea...................................... 147 10.6 Conclusion............................................... 148 5 Overview The Societal Energy Problem We are being made aware almost every day of an approaching energy crisis. There seems to be no such thing as free energy, energy without cost. Continu- ing consumption of fossil fuels will almost certainly result in damaging climate change, and all the alternatives come with a range of drawbacks. Addressing the problem is becoming critical, and is likely to become the most important societal challenge of the next 50 years. There is a huge dependence on concentrated energy sources to power our technology. The unrelenting industrialisation of modern society continues to be powered by rich energy sources found within the earth. Energy from the sun that was captured by plant life over millions of years has accumulated in the ground as dead organic matter. Heat and pressure underground have cooked the organic molecules into familiar hydrocarbon mixtures such as oil, coal and gas. These fossil fuels began being removed from the ground in the 19th century to provide the raw energy needed to drive the industrial revolution, and fossil fuels still continue to be extracted from the earth in vast quantities and now work just about everything around us. But what has taken millions of years to accumulate in deep stores within the earth, we seemingly are blithely raiding and will perhaps consume in a mere two hundred years. Scarcity must eventually become a problem for a world that is heavily de- pendent on fossil fuels and it seems like this dependence is growing as more and more of the world becomes industrialised. What will we do when there is no fossil fuel left? And are there any alternative sources of energy? Whatever the answer to these questions, change seems inevitable. Changes in the way energy is produced and consumed will have to take place and will have a huge impact on the individual and society, and there is an increasing belief that making a significant transition now (through choice) from cheap reliable energy to the renewable energy that is available all around will ultimately benefit everyone. Energy will be extracted as required from what is available around about, without a need to draw on the energy of the past (or the future). The ‘new’ energy will likely be unreliable, intermittent and difficult to capture in sufficient quantity; we will have to take it as it comes – it will not be available ‘on tap’ just as we want it and it may not be feasible to use energy in the same wasteful and reckless way we currently do. And it is not solely a matter of supply and demand - there is the additional problem of climate change associated with the burning of carbon. A rising at- mospheric carbon dioxide concentration is likely to result in an overall global temperature rise. However, the uncertainties on the modelling process used to anticipate future effects makes it hard to predict what will really happen: pre- dictions range from a runaway greenhouse making the planet uninhabitable, to a 300 year blip which disappears into a highly variable temperature history as the planet self regulates after most of the available
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