Astronomy Freshman Seminars 2016-17

 

ASTEROIDS AND COMETS

Charles R. Alcock (Department of Astronomy) Freshman Seminar 23R 4 credits (fall term) Enrollment: Limited to 12 Note: The seminar will make use of the Clay Telescope on the roof of the Science Center. There may also be a trip to the Observatory at 60 Garden Street to visit the Great Refractor.

Comets have been seen regularly since before the beginning of recorded history. They have often been regarded as disturbing portents. Asteroids, on the other hand, were not discovered until the 19th century, with the advent of astronomy with telescopes. Today we know of many more asteroids than comets, but we believe that there are vastly more comets than asteroids in the solar system. This seminar will start with the history of the study of comets and asteroids, including the “Great March Comet of 1843,” observations of which led to the establishment of the Harvard College Observatory and its Great Refractor, at the time the largest telescope in the Americas. Our understanding of comets advanced dramatically in 1950 with the publication of two extraordinary papers: Whipple (then at Harvard) described the mixture of dust and ice that comprises the nuclei of comets, and Oort (Leiden University) showed that new comets enter the inner solar system from a vast, diffuse cloud surrounding the planetary system. Modern telescopes and spacecraft encounters provide us today with a wealth of information about comets and asteroids. We will examine these observations and learn what is known and what is inferred about the origin and structure of asteroids and comets. The students will observe with the Astronomy Laboratory’s Clay Telescope on the roof of the Science Center. Students will take on projects, which may involve their own observing program, or which exploit existing data.

 

BLACK HOLES, STRING THEORY AND THE FUNDAMENTAL LAWS OF NATURE

Andrew Strominger (Department of Physics) Freshman Seminar 21V 4 credits (fall term) Enrollment: Limited to 12 Prerequisite: High school level calculus and physics

The quest to understand the fundamental laws of nature has been ongoing for centuries. This seminar will assess the current status of this quest. In the first five weeks, we will cover the basic pillars of our understanding: Einstein’s theory of general relativity, quantum mechanics and the Standard Model of particle physics. We will then examine the inadequacies and inconsistencies in our current picture, including, for example, the problem of quantum gravity, the lack of a unified theory of forces, Dirac’s large numbers problem, the cosmological constant problem, Hawking’s black hole information paradox, and the absence of a theory for the origin of the universe. Attempts to address these issues and move beyond our current understanding involve a network of intertwined investigations in string theory, M theory, inflation and non-abelian gauge theories and have drawn inspiration from the study of black holes and developments in modern mathematics. These forays beyond the edge of our current knowledge will be reviewed and assessed. The format of the course will be discussion of weekly reading assignments and a final paper. Non-scientists are welcome. COSMIC EXPLOSIONS Edo Berger (Department of Astronomy) Freshman Seminar 21C 4 credits (spring term) Enrollment: Limited to 12 Somewhere in the universe a massive star ends its life in a supernova explosion every second (you can count: “1 supernova, 2 supernova, 3 supernova…”). These supernovae, and other types of cosmic explosions like them, play a critical role in shaping the universe. They are responsible for the synthesis and dispersal of all the chemical elements heavier than hydrogen and helium, and, therefore, provide the building blocks for the next generations of stars, for planets and ultimately for life. These cosmic explosions also give birth to exotic objects, such as neutron stars and black holes. Finally, the explosions are so powerful that they can influence the formation of new stars within their galaxies. In this seminar, we will explore how different types of cosmic explosions occur and how they influence the universe and life within it. Equally important, we will actually use telescopes in Cambridge and in Arizona to study a new supernova explosion during the semester.

 

HOW DID THE FIRST STARS AND GALAXIES FORM?

Abraham Loeb (Department of Astronomy) Freshman Seminar 21G 4 credits (spring term) Enrollment: Limited to 12

 Since the universe is expanding, it must have been denser in the past. But even before we get all the way back to the Big Bang, there must have been a time when stars like our sun or galaxies like our own Milky Way did not exist, because the universe was denser than they are. We, therefore, face the important question about our origins: How and when did the first stars and galaxies form? Primitive versions of this question were considered by humans in religious and philosophical texts for thousands of years, long before it was realized that the universe expands. The Seminar will summarize the fundamental principles and scientific ideas that are being used to address this question in modern cosmology. Previous generations of scholars have also wondered about the long-term future of the universe. For the first time in history, we now have a standard cosmological model that agrees with a large body of data about the past history of the universe. The seminar will conclude with the forecast that this scientific model makes about our future. It will be based on a book with the same title written by Professor Loeb (Princeton University Press, 2010). PHYSICS AND BIG QUESTIONS Gerald Gabrielse (Department of Physics) Freshman Seminar 22V 4 credits (spring term) Enrollment: Limited to 12 Three types of big questions will be considered. The first are the big questions about the limits and domain of physics. To start, what are the limits and domain of applicability of the classical physics studies studied in high school? How do these relate to special relativity, quantum mechanics and quantum field theory? Next, what are some of the big questions that physics seeks to answer. For example, what is the “standard model” of particle physics, and how is it tested? Other important big questions relate to how physics informs some major challenges to our society. For example, what does physics say about the options for powering our homes and cars, given limited petroleum reserves and the need to reduce carbon dioxide production? The final set of big questions is about the compatibility or incompatibility of physics and religious faith. Here we will consider very divergent answers in a climate of respect for what will be big differences in opinion.

 

PHYSICS, MATH AND PUZZLES

Cumrun Vafa (Department of Physics) Freshman Seminar 23P 4 credits (fall term) Enrollment: Limited to 15 Prerequisite: This seminar is recommended for students with a strong background in both math and physics and with keen interest in the relation between the two subjects. Physics is a highly developed branch of science with a broad range of applications. Despite the complexity of the universe, the fundamental laws of physics are rather simple, if viewed properly. This seminar will focus on intuitive as well as mathematical underpinnings of some of the fundamental laws of nature. The seminars will use mathematical puzzles to introduce the basic features of physical laws. Main aspects discussed include the role of symmetries as well as the power of modern math, including abstract ideas in topology, in unraveling the mysteries of the universe. Examples are drawn from diverse areas of physics including string theory. The issue of why the universe is so big, as well as its potential explanation is also discussed.

 

QUANTUM MECHANICS FACE TO FACE

Melissa Franklin (Department of Physics) Freshman Seminar 22S 4 credits (spring term) Enrollment: Limited to 12

This course is for students who would like to be introduced to the ideas of quantum mechanics without the rigor of mathematics, but who would be interested in learning by demonstration as well as spoken word and picture. We will be guided by a non-mathematical text, Introducing Quantum Theory, read short pieces by the creators of quantum theory, including Bohr, Einstein, Hesienberg and Schrodinger, and each week watch and play with physics demonstrations of wave and particle physics. This course requires reading, watching short films, watching demonstrations in the lab and visiting places at the university where quantum mechanics is used on a daily basis. THE TEMPORAL UNIVERSE Jonathan E. Grindlay (Department of Astronomy) Freshman Seminar 50I 4 credits (spring term) Enrollment: Limited to 12 Note: This seminar is open to all but may be of particular interest to those considering physical science or engineering concentrations. The universe is not static, but rather stars and entire galaxies are evolving as revealed by their variability on timescales ranging from giga-years for galaxies to milliseconds for collapsed stars (neutron stars and black holes). In this seminar, we shall explore stars and galaxies through variability—from how brightness variability of stars with binary companions measured with small telescopes measures star masses and radii, to the extremes of variability of stars that undergo repeated huge flares, to enormously luminous variations from accretion onto gargantuan black holes in the nuclei of “Active Galaxies” (Blazars and Quasars). We shall use the Clay Telescope on the Science Center roof to make some repeated observations (from the 8th floor Astronomy Lab) of an example of each of these two types of variable stars and deduce what life would be like if either were our sun. From a Blazar, we shall observe historical outbursts that occasionally change brightness to exceed its host galaxy by a factor of ~100, by using the digitized brightness measures of this object on thousands of glass-plate images taken by Harvard telescopes from 1885 to 1992 and now digitized and online from our Digital Access to a Sky Century @ Harvard (DASCH) project. The seminar will include readings from an introductory astronomy text, as well as both popular and journal articles and the short book Black Hole (Bartusiak). Students will use astronomical software to measure stellar brightness and variability from telescope images, as well as learn temporal analysis techniques with applications to other disciplines. Students discuss in class readings and observations conducted and write short papers on their observations and deductions.

 

 

COSMIC EXPLOSIONS

Edo Berger (Department of Astronomy) Freshman Seminar 21C 4 credits (spring term) Enrollment: Limited to 12

Somewhere in the universe a massive star ends its life in a supernova explosion every second (you can count: “1 supernova, 2 supernova, 3 supernova…”). These supernovae, and other types of cosmic explosions like them, play a critical role in shaping the universe. They are responsible for the synthesis and dispersal of all the chemical elements heavier than hydrogen and helium, and, therefore, provide the building blocks for the next generations of stars, for planets and ultimately for life. These cosmic explosions also give birth to exotic objects, such as neutron stars and black holes. Finally, the explosions are so powerful that they can influence the formation of new stars within their galaxies. In this seminar, we will explore how different types of cosmic explosions occur and how they influence the universe and life within it. Equally important, we will actually use telescopes in Cambridge and in Arizona to study a new supernova explosion during the semester.


PHYSICS AND BIG QUESTIONS

Gerald Gabrielse (Department of Physics) Freshman Seminar 22V 4 credits (spring term) Enrollment: Limited to 12

Three types of big questions will be considered. The first are the big questions about the limits and domain of physics. To start, what are the limits and domain of applicability of the classical physics studies studied in high school? How do these relate to special relativity, quantum mechanics and quantum field theory? Next, what are some of the big questions that physics seeks to answer. For example, what is the “standard model” of particle physics, and how is it tested? Other important big questions relate to how physics informs some major challenges to our society. For example, what does physics say about the options for powering our homes and cars, given limited petroleum reserves and the need to reduce carbon dioxide production? The final set of big questions is about the compatibility or incompatibility of physics and religious faith. Here we will consider very divergent answers in a climate of respect for what will be big differences in opinion.


THE TEMPORAL UNIVERSE 

Jonathan E. Grindlay (Department of Astronomy) Freshman Seminar 50I 4 credits (spring term) Enrollment: Limited to 12 Note: This seminar is open to all but may be of particular interest to those considering physical science or engineering concentrations.

The universe is not static, but rather stars and entire galaxies are evolving as revealed by their variability on timescales ranging from giga-years for galaxies to milliseconds for collapsed stars (neutron stars and black holes). In this seminar, we shall explore stars and galaxies through variability—from how brightness variability of stars with binary companions measured with small telescopes measures star masses and radii, to the extremes of variability of stars that undergo repeated huge flares, to enormously luminous variations from accretion onto gargantuan black holes in the nuclei of “Active Galaxies” (Blazars and Quasars). We shall use the Clay Telescope on the Science Center roof to make some repeated observations (from the 8th floor Astronomy Lab) of an example of each of these two types of variable stars and deduce what life would be like if either were our sun. From a Blazar, we shall observe historical outbursts that occasionally change brightness to exceed its host galaxy by a factor of ~100, by using the digitized brightness measures of this object on thousands of glass-plate images taken by Harvard telescopes from 1885 to 1992 and now digitized and online from our Digital Access to a Sky Century @ Harvard (DASCH) project. The seminar will include readings from an introductory astronomy text, as well as both popular and journal articles and the short book Black Hole (Bartusiak). Students will use astronomical software to measure stellar brightness and variability from telescope images, as well as learn temporal analysis techniques with applications to other disciplines. Students discuss in class readings and observations conducted and write short papers on their observations and deductions.