25 – Suicide, Part II: Deciding under Uncertainty

25 – Suicide, Part II: Deciding under Uncertainty

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The discussion of suicide continues. A few more cases are introduced to consider circumstances under which it might be rational to end one’s life, and more graphs are drawn that show relevant variations in the quality of one’s life. A question is then posed about how one should make a decision about continuing or ending life, given that one cannot know the future with certainty. Finally, two quick moral arguments concerning suicide which rest on theological premises are presented.

22 – Supernovae

22 – Supernovae

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Professor Bailyn offers a review of what is known so far about the expansion of the universe from observing galaxies, supernovae, and other celestial phenomena. The rate of the expansion of the universe is discussed along with the Big Rip theory and the balance of dark energy and dark matter in the universe over time. The point at which the universe shifts from accelerating to decelerating is examined. Worries related to the brightness of high redshift supernovae and the effects of gravitational lensing are explained. The lecture also describes current project designs for detecting supernovae at high or intermediate redshift, such as the Joint Dark Energy Mission (JDEM) and Large Synoptic Survey Telescope (LSST).

24 – Suicide, Part I: The Rationality of Suicide

24 – Suicide, Part I: The Rationality of Suicide

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This is the first of a series of lectures on suicide. Two very distinct contexts are presented in which the subject can be further explored. The first is rationality and the question of under what circumstances it makes sense to end one’s own life. The second is morality and the question of whether we can ever ethically justify resorting to suicide. The lecture’s focus is on the rational requirements of suicide, and Professor Kagan introduces a number of cases which demonstrate that ending one’s life, in certain instances, may be rationally sound.

21 – Dark Energy and the Accelerating Universe and the Big Rip

21 – Dark Energy and the Accelerating Universe and the Big Rip

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Class begins with a review of the mysterious nature of dark matter, which accounts for three quarters of the universe. Different models of the universe are graphed. The nature, frequency, and duration of supernovae are then addressed. Professor Bailyn presents data from the Supernova Cosmology Project and pictures of supernovae taken by the Hubble Space Telescope. The discovery of dark energy is revisited and the density of dark energy is calculated. The Big Rip is presented as an alternative hypothesis for the fate of the universe.

23 – How to Live Given the Certainty of Death

23 – How to Live Given the Certainty of Death

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In this lecture, Professor Kagan invites students to pose the question of how one should live life knowing that it will certainly end in death. He also explores the issue of how we should set our goals and how we should go about achieving them, bearing in mind the time constraints. Other questions raised are how this ultimately affects the quality of our work and our accomplishments, as well as how we decide what is worth doing in life.

20 – Dark Matter

20 – Dark Matter

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This lecture introduces an important concept related to the past and future of the universe: the Scale factor, which is a function of time. With reference to a graph whose coordinates are the Scale factor and time, the problem of dark matter is addressed again. Cosmological redshifts are measured to determine the scale of the universe. The discovery of the repulsive, anti-gravitational force of dark energy is explained. The lecture concludes with discussion of Einstein’s biggest mistake: the invention of the cosmological constant to balance gravity.

22 – Fear of Death

22 – Fear of Death

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Professor Kagan explores the issue of how thinking about death may influence the way we live. Fear as an emotional response to death is discussed as well as whether it is appropriate and under what conditions. A distinction is made between fear of the process of dying, and fear of death itself and what may come when one is dead. Finally, a number of other negative emotions are considered as possible appropriate responses to death and dying, such as anger, sadness, and sorrow.

19 – Omega and the End of the Universe

19 – Omega and the End of the Universe

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Class begins with a review of the issues previously addressed about the origin and fate of the universe. The role of gravity in the expansion of the universe is discussed and given as the reason why the rate of expansion cannot remain constant and will eventually slow down. The actual density of the universe is calculated using various methods. Finally, the unsolved problem of dark matter is addressed and two explanatory hypotheses are proposed. One is that the universe is comprised of WIMPs (Weakly Interactive Massive Particles) that fulfill two requirements: they have mass and do not interact with light. The second hypothesis is that dark matter is made of MACHOs (Massive Astrophysical Compact Halo Objects), which scientists have attempted to identify through gravitational lenses.

21 – Other Bad Aspects of Death, Part II

21 – Other Bad Aspects of Death, Part II

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Further bad aspects of death are considered, including ubiquity, or the fact that death may occur at any time and strike anyone. Professor Kagan invites students to contemplate the possibility of death-free time periods, vacation spots, and activities. Then there is consideration of the value of the human condition, which consists of life, followed by death. Finally, the question is raised as to whether it could be appropriate to refuse to face the facts about our mortality. Professor Kagan distinguishes between two ways in which thinking about these could influence human behavior. On the one hand, it may give one the reason to behave differently; on the other hand, it may just cause a change in behavior.

18 – Hubble’s Law and the Big Bang pt 3

18 – Hubble’s Law and the Big Bang pt 3

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Professor Bailyn returns to the subject of the expansion of the universe to offer explanations that do not require belief in the Big Bang theory. One alternative is a theory that, in the past, the entire universe was reduced to an “initial singularity,” in which everything was much closer, and therefore denser and hotter. Since the universe is in constant flux, however, it follows that in the future things will drift apart. The Steady State explanation for the expansion of the universe is then explained. Coined as a derogatory term meant to ridicule supporters of the Big Bang theory, Steady State purports that new energy and matter are constantly created as the universe expands, to fill in the void that results from the expansion. The discovery of quasars refuted the Steady State theory. The lecture ends with a discussion of how observing very distant objects allows us to look back in time, and also gives us a glimpse into the future of galaxies and the universe.