Leonard Hofstadter
Encyclopedia
Leonard Leakey Hofstadter, Ph.D.
, is a fictional character on the CBS
television series The Big Bang Theory
, portrayed by actor Johnny Galecki
. Leonard is an experimental physicist
from New Jersey who shares an apartment with colleague and best friend Sheldon Cooper
(Jim Parsons
). Leonard and Sheldon are named after actor/producer Sheldon Leonard
, and Nobel Prize
Laureates Robert Hofstadter
and Leon Cooper
.
Leonard has been described as the straight man
of the series. Penny
(Kaley Cuoco
) is Leonard's next-door neighbor and main love interest, and the teasing of romance between the two of them is a major force driving the series. In 2011, Galecki was nominated for a Primetime Emmy Award for Outstanding Lead Actor in a Comedy Series.
, and a graduate of Princeton University, Leonard works as a Caltech
experimental physicist
who shares an apartment with colleague Sheldon Cooper
in Pasadena
, California
. He is usually seen wearing his characteristic black framed glasses, low-cut black Converse All Stars sneakers, neutral-colored sweat jackets, brown trousers, and physics-themed t-shirts.
Although Leonard feels at home with his geek
colleagues, he wants to be more social. Among the main characters, he generally has the least amount of difficulty interacting with "non-geek" individuals. He is instantly captivated by Penny
, and from the beginning sets out to date her.
In early episodes, Leonard is reluctant to let Penny know about his recreational activities (such as Klingon
Boggle
), as he does not want her to see him as a geek. While certainly a geek by most definitions, he is less socially awkward than Sheldon (who is unable to grasp social norms), Raj
(who is unable to talk to women unless he is under the influence of alcohol), and even Howard
(who is often seen as "creepy" when flirting with women).
Leonard can also play the cello
. As seen in the season 1 episode "The Hamburger Postulation", he and Leslie Winkle practice their instruments and then leave to have sex.
Despite his attempts to not appear to be a geek, Leonard owns, among other things, Star Wars
hygiene products, an expansive Superman
comic book collection (and wears Clark Kent
-type glasses) and a Battlestar Galactica
Colonial warrior's flight suit. Early in the series, Leonard tried to get rid of his collectables to impress Penny with his maturity. However, he changed his mind when he saw Penny was already dating another man.
Having lived with Sheldon for several years, Leonard knows him best, and is obligated to explain Sheldon's behavior, and/or serve as a mediator between him and other people in many situations. For instance, when Penny and Sheldon engaged in a fierce dispute, Leonard gave Penny the phone number of Sheldon's mother so she would call her son and scold him for his behavior, thus ending the fight.
Leonard's primary health concern is his lactose intolerance
; he avoids eating even small amounts of dairy products, including cheese, yoghurt, and butter, for fear of passing gas
. According to the (unaired) pilot, he cannot process corn either. Leonard also wears glasses because of myopia
, and practically cannot see without them. On one occasion, when his glasses were broken at the movie theater, he had to surreptitiously return to his apartment and retrieve his backup glasses. In order to avoid detection by a sick Sheldon and Penny, who was nursing him, Howard
and Raj
helped him to navigate through the living room by using a helmet camera
. Leonard states in one episode that he suffers from sleep apnea
. During his relationship with Leslie Winkle, he tells her that many members of his family have died from heart disease and thus he has a genetic disposition to the condition.
At various points in the show, Sheldon also says that Leonard gets carsick unless he sits in the front seat.
.
Leonard's mother, Dr. Beverly Hofstadter, is a psychiatrist
and neuroscientist
. She has a personality almost identical to Sheldon's, including strict speech patterns, lack of social conventions, and attention to detail, and is principally responsible for Leonard's difficult childhood. Due to his mother's views, Leonard never celebrated his birthday
when he was a child, and when she visited him she was not impressed with his unoriginal research. Leonard revealed to Penny that when he was young he built a "hugging machine" in order to compensate for the lack of affection from his mother. He further stated that his father used to borrow it. Beverly also belittles Leonard by pointing out that his brother and sister are more successful in their respective fields than he is. Leonard's brother, Michael, is a Harvard law professor and is engaged to the youngest appellate court judge in New Jersey
history, and his sister is a cutting-edge medical researcher working with gibbon
s to cure diabetes.
Leonard's father is briefly mentioned as an anthropologist. Sheldon reveals that Leonard's middle name, "Leakey", comes from famed archaeologist Louis Leakey
, with whom Leonard's father had worked. Leonard is embarrassed by this middle name and its humorous connotations, and rarely mentions it.
Though little is known about Leonard's extended family, a few references to it have been made. In the first episode, Sheldon and Leonard discuss Leonard's grandmother, who had visited them on Thanksgiving
the year before. She has Alzheimer's disease
and apparently "had an episode" during her visit, which resulted in her stripping off her clothes and carving the turkey. On Beverly's first visit, she tells Leonard that his uncle Floyd has died, which greatly upsets him (according to him, Floyd was the only family member he really liked). Leonard also has several other uncles, which Sheldon says are all very bald, and when they gather together, they look "like a half carton of eggs". Leonard describes his aunt, however, as being "one of the hairiest women you will ever meet".
of 173, and was 24 years old when he received his Ph.D
from Princeton University
. Dr. Hofstadter received a dissertation of the year award for his doctoral paper on experimental particle physics
.
Leonard's work as an experimental physicist often includes the use of laser
s, such as a helium-neon laser
or free-electron laser, and his research topics have varied from Bose-Einstein condensates and foundations of quantum mechanics
to soft cosmic ray
s at sea level and development of novel rocket propellants. Leonard designs experiments in order to prove theories but, according to the cynical and egotistical theorist Sheldon
, his work is mostly derivative and thus unimportant.
His miscalculations in loading the top secret propellant for Howard's rocket led to the elevator in the apartment building where he lives being out of service for several years and his attempts to disprove the existence of dark matter
were made moot by the work of another physicist. Yet, he resolved the latter by helping to solidify proof of the hypothetical matter's existence with a photomultiplier
, was invited as keynote speaker to a topical conference by the Institute of Experimental Physics for his successful research on supersolid
s and has showed diverse knowledge of theoretical physics
.
within seconds of spotting her. His infatuation with Penny becomes the major force that drives the series during the first seasons. By the end of the first season
, Leonard finally managed to ask Penny out, and they had their first date. Subsequently, they broke up because Penny felt she wasn't as smart as Leonard would like.
Besides Penny, Leonard has been involved with only a few other women. One of Leonard's former girlfriends that is mentioned in several occasions is Joyce Kim. Although she has only recently appeared in person, Leonard's friends recalled on many occasions that they were together for only 27 days, after which Joyce, later revealed to be a spy
, defected to North Korea
.
Initially, after feeling that Penny was not for him, Leonard turned his attention to fellow scientist Leslie Winkle. The first time Leonard asked Leslie out, she rejected him, and his further relationships with her proved to be only short-lived casual sex
encounters at her whim.
In the second season, Leonard began a stable relationship with Dr. Stephanie Barnett. Although the relationship went well, even earning Sheldon's approval, Leonard felt uncomfortable with Stephanie moving in with him, and the relationship was ended off-screen.
On another occasion, when Leonard's mother was visiting, he and Penny came very close to having sex
, but Leonard ruined the moment by talking about their childhood issues with his mother and her father, respectively. In the second season finale, when Leonard, Sheldon, Howard, and Raj were due to leave for a three-month scientific expedition to the North Pole
, Penny finally showed interest in Leonard, but kept her feelings a secret from him.
In the third season premiere
, Leonard and Penny finally started a romantic relationship and had sex for the first time.
However, the relationship ended after Leonard prematurely told Penny he loved her and she realized she could not yet reciprocate. In order to win a bowling
match against Sheldon's team, which included Leonard and Penny, Wil Wheaton picked up on the tension between Penny and Leonard and manipulated her into dumping him to break up the team. Shortly after the breakup, Leonard has a one-night stand
with a physicist he admires when she stays with him on a short visit, causing anger and open disgust from Penny. Leonard and Penny later resolve their feelings and their friendship continues.
In the third season finale, after Penny's failed attempts to move on from her relationship with Leonard, she gets drunk and has sex with him. In the morning, Leonard believes that their relationship has resumed, though Penny tells him that having sex with him was a mistake. This causes a strain on their friendship; at the end of the episode, Leonard gets drunk and tries to have sex with her, prompting Penny to kick him out of her apartment.
Leonard also has an affair with Raj's younger sister Priya (apparently every time she comes to town), despite a pinky swear with Howard that neither of them would attempt to make a move on her, and Raj giving his strong disapproval.
When Penny's father Wyatt comes to town, she pretends she is still with Leonard so as not to disappoint her father. Her father had apparently been extremely glad to learn she was finally dating a man who was not an idiot (according to his mindset). When he discovers the ruse, he begs Leonard not to give up on Penny.
Throughout the fourth season, it becomes obvious that Penny is still in love with Leonard. It is unclear whether or not Leonard has noticed this, though he clearly is still interested in Penny. In "The Benefactor Factor", a woman propositions Leonard in exchange for a large donation to the physics department; he initially resists and she admits that she planned to make the donation anyway, after which they engage in a one-night stand. Leonard arrives home the next morning, whereupon Penny recognizes his "walk of shame" and Sheldon thinks Leonard has a future in becoming a gigolo
to rich ladies in exchange for donations.
When Priya returns, she and Leonard begin a relationship. Raj strongly opposes this, and Penny is secretly uncomfortable with Leonard dating someone else, eventually breaking down and crying while talking with her friend Amy Farrah Fowler. Once again, Leonard is unaware of Penny's true feelings. More recently, Priya pressures Leonard into telling Penny to leave him alone, which he does, albeit extremely reluctantly. Penny complies, though it is clear that she does not want Leonard out of her life. Penny eventually figures out how to stay in Leonard's life: by buddying up to Priya, which actually works.
In the Season 4 finale, Leonard runs into Penny and Raj as they come out of his room in the morning, just after Leonard and Priya appear to break up upon Leonard's learning that Priya is soon moving back to India
. At the start of Season 5, Leonard and Priya are trying to maintain a long-distance relationship via Skype
(including a failed attempt at cybersex
) with Priya continuing to treat Leonard like a submissive partner. Despite being the most eager to have sex, Leonard proves here he is extremely awkward in these situations. Leonard later goes to a wedding with Amy, and they seem to take a liking to each other, though Sheldon disapproves, karate-chopping Leonard and saying, "She's not for you...not for you!". Later, despite feeling that he and Priya were in love and might get married, Leonard finds himself attracted to a comic book artist named Alice. The attraction is mutual, and they even share a kiss. Right when they are about to have sex, however, he tells Alice that he has a girlfriend, thus ending the relationship. Leonard then decides to confess his behavior to Priya on Skype, but he is shocked to learn that Priya has also cheated on him, sleeping with her ex-boyfriend. In the next episode, Leonard tells Sheldon that he is single, implying that he and Priya have broken up.
Doctor of Philosophy
Doctor of Philosophy, abbreviated as Ph.D., PhD, D.Phil., or DPhil , in English-speaking countries, is a postgraduate academic degree awarded by universities...
, is a fictional character on the CBS
CBS
CBS Broadcasting Inc. is a major US commercial broadcasting television network, which started as a radio network. The name is derived from the initials of the network's former name, Columbia Broadcasting System. The network is sometimes referred to as the "Eye Network" in reference to the shape of...
television series The Big Bang Theory
The Big Bang Theory
The Big Bang Theory is an American sitcom created by Chuck Lorre and Bill Prady, both of whom serve as executive producers on the show, along with Steven Molaro. All three also serve as head writers...
, portrayed by actor Johnny Galecki
Johnny Galecki
John Mark "Johnny" Galecki is an American actor. He is best known for his roles as David Healy in the ABC sitcom Roseanne, Rusty Griswold in National Lampoon's Christmas Vacation, and as Leonard Hofstadter in the CBS sitcom The Big Bang Theory.-Early life:Galecki was born in Bree, Belgium, of...
. Leonard is an experimental physicist
Physicist
A physicist is a scientist who studies or practices physics. Physicists study a wide range of physical phenomena in many branches of physics spanning all length scales: from sub-atomic particles of which all ordinary matter is made to the behavior of the material Universe as a whole...
from New Jersey who shares an apartment with colleague and best friend Sheldon Cooper
Sheldon Cooper
Sheldon Lee Cooper, B.S., M.S., M.A., Ph.D., Sc.D. is a fictional character from Texas on the CBS television series The Big Bang Theory, portrayed by actor Jim Parsons...
(Jim Parsons
Jim Parsons
James Joseph "Jim" Parsons is an American television and film actor. He is best known for playing Sheldon Cooper on the CBS sitcom The Big Bang Theory, with his performance often cited as a significant reason for the program's success...
). Leonard and Sheldon are named after actor/producer Sheldon Leonard
Sheldon Leonard
Sheldon Leonard was a pioneering American film and television producer, director, writer, and actor.-Biography:...
, and Nobel Prize
Nobel Prize
The Nobel Prizes are annual international awards bestowed by Scandinavian committees in recognition of cultural and scientific advances. The will of the Swedish chemist Alfred Nobel, the inventor of dynamite, established the prizes in 1895...
Laureates Robert Hofstadter
Robert Hofstadter
Robert Hofstadter was an American physicist. He was the joint winner of the 1961 Nobel Prize in Physics "for his pioneering studies of electron scattering in atomic nuclei and for his consequent discoveries concerning the structure of nucleons."-Biography :Born in New York City, he entered City...
and Leon Cooper
Leon Cooper
Leon N Cooper is an American physicist and Nobel Prize laureate, who with John Bardeen and John Robert Schrieffer, developed the BCS theory of superconductivity...
.
Leonard has been described as the straight man
Double act
A double act, also known as a comedy duo, is a comic pairing in which humor is derived from the uneven relationship between two partners, usually of the same gender, age, ethnic origin and profession, but drastically different personalities or behavior...
of the series. Penny
Penny (The Big Bang Theory)
Penny is a fictional character on the CBS television series The Big Bang Theory, portrayed by American actress Kaley Cuoco.Penny is the main female character on the show. She is Leonard Hofstadter and Sheldon Cooper's neighbor across the hallway, and the main love interest of Leonard...
(Kaley Cuoco
Kaley Cuoco
Kaley Christine Cuoco is an American film and television actress. She first came to attention for her role as Bridget Hennessy on the Emmy Award-winning sitcom 8 Simple Rules. She later starred as Billie Jenkins on the final season of the supernatural drama series Charmed...
) is Leonard's next-door neighbor and main love interest, and the teasing of romance between the two of them is a major force driving the series. In 2011, Galecki was nominated for a Primetime Emmy Award for Outstanding Lead Actor in a Comedy Series.
Personality
Originally from New JerseyNew Jersey
New Jersey is a state in the Northeastern and Middle Atlantic regions of the United States. , its population was 8,791,894. It is bordered on the north and east by the state of New York, on the southeast and south by the Atlantic Ocean, on the west by Pennsylvania and on the southwest by Delaware...
, and a graduate of Princeton University, Leonard works as a Caltech
California Institute of Technology
The California Institute of Technology is a private research university located in Pasadena, California, United States. Caltech has six academic divisions with strong emphases on science and engineering...
experimental physicist
Physicist
A physicist is a scientist who studies or practices physics. Physicists study a wide range of physical phenomena in many branches of physics spanning all length scales: from sub-atomic particles of which all ordinary matter is made to the behavior of the material Universe as a whole...
who shares an apartment with colleague Sheldon Cooper
Sheldon Cooper
Sheldon Lee Cooper, B.S., M.S., M.A., Ph.D., Sc.D. is a fictional character from Texas on the CBS television series The Big Bang Theory, portrayed by actor Jim Parsons...
in Pasadena
Pasadena, California
Pasadena is a city in Los Angeles County, California, United States. Although famous for hosting the annual Rose Bowl football game and Tournament of Roses Parade, Pasadena is the home to many scientific and cultural institutions, including the California Institute of Technology , the Jet...
, California
California
California is a state located on the West Coast of the United States. It is by far the most populous U.S. state, and the third-largest by land area...
. He is usually seen wearing his characteristic black framed glasses, low-cut black Converse All Stars sneakers, neutral-colored sweat jackets, brown trousers, and physics-themed t-shirts.
Although Leonard feels at home with his geek
Geek
The word geek is a slang term, with different meanings ranging from "a computer expert or enthusiast" to "a carnival performer who performs sensationally morbid or disgusting acts", with a general pejorative meaning of "a peculiar or otherwise dislikable person, esp[ecially] one who is perceived to...
colleagues, he wants to be more social. Among the main characters, he generally has the least amount of difficulty interacting with "non-geek" individuals. He is instantly captivated by Penny
Penny (The Big Bang Theory)
Penny is a fictional character on the CBS television series The Big Bang Theory, portrayed by American actress Kaley Cuoco.Penny is the main female character on the show. She is Leonard Hofstadter and Sheldon Cooper's neighbor across the hallway, and the main love interest of Leonard...
, and from the beginning sets out to date her.
In early episodes, Leonard is reluctant to let Penny know about his recreational activities (such as Klingon
Klingon language
The Klingon language is the constructed language spoken by the fictional Klingons in the Star Trek universe....
Boggle
Boggle
Boggle is a word game designed by Allan Turoff and trademarked by Parker Brothers, a division of Hasbro. The game is played using a plastic grid of lettered dice, in which players attempt to find words in sequences of adjacent letters.-Rules:...
), as he does not want her to see him as a geek. While certainly a geek by most definitions, he is less socially awkward than Sheldon (who is unable to grasp social norms), Raj
Rajesh Koothrappali
Rajesh Ramayan "Raj" Koothrappali, Ph.D. is a fictional character on the CBS television series The Big Bang Theory, portrayed by actor Kunal Nayyar....
(who is unable to talk to women unless he is under the influence of alcohol), and even Howard
Howard Wolowitz
Howard Joel Wolowitz, M.Eng is a fictional character on the CBS television series The Big Bang Theory, portrayed by actor Simon Helberg.Among the main male characters in the show, Howard is distinguished for lacking a doctoral degree, for still living with his mother, and for believing himself to...
(who is often seen as "creepy" when flirting with women).
Leonard can also play the cello
Cello
The cello is a bowed string instrument with four strings tuned in perfect fifths. It is a member of the violin family of musical instruments, which also includes the violin, viola, and double bass. Old forms of the instrument in the Baroque era are baryton and viol .A person who plays a cello is...
. As seen in the season 1 episode "The Hamburger Postulation", he and Leslie Winkle practice their instruments and then leave to have sex.
Despite his attempts to not appear to be a geek, Leonard owns, among other things, Star Wars
Star Wars
Star Wars is an American epic space opera film series created by George Lucas. The first film in the series was originally released on May 25, 1977, under the title Star Wars, by 20th Century Fox, and became a worldwide pop culture phenomenon, followed by two sequels, released at three-year...
hygiene products, an expansive Superman
Superman
Superman is a fictional comic book superhero appearing in publications by DC Comics, widely considered to be an American cultural icon. Created by American writer Jerry Siegel and Canadian-born American artist Joe Shuster in 1932 while both were living in Cleveland, Ohio, and sold to Detective...
comic book collection (and wears Clark Kent
Clark Kent
Clark Kent is a fictional character created by Jerry Siegel and Joe Shuster. Appearing regularly in stories published by DC Comics, he debuted in Action Comics #1 and serves as the civilian and secret identity of the superhero Superman....
-type glasses) and a Battlestar Galactica
Battlestar Galactica (1978 TV series)
Battlestar Galactica is an American science fiction television series, created by Glen A. Larson. It starred Lorne Greene, Richard Hatch and Dirk Benedict and ran for one season in 1978–79. After cancellation, its story was continued in 1980 as Galactica 1980 with Adama, Lieutenant Boomer and...
Colonial warrior's flight suit. Early in the series, Leonard tried to get rid of his collectables to impress Penny with his maturity. However, he changed his mind when he saw Penny was already dating another man.
Having lived with Sheldon for several years, Leonard knows him best, and is obligated to explain Sheldon's behavior, and/or serve as a mediator between him and other people in many situations. For instance, when Penny and Sheldon engaged in a fierce dispute, Leonard gave Penny the phone number of Sheldon's mother so she would call her son and scold him for his behavior, thus ending the fight.
Leonard's primary health concern is his lactose intolerance
Lactose intolerance
Lactose intolerance, also called lactase deficiency or hypolactasia, is the inability to digest and metabolize lactose, a sugar found in milk...
; he avoids eating even small amounts of dairy products, including cheese, yoghurt, and butter, for fear of passing gas
Flatulence
Flatulence is the expulsion through the rectum of a mixture of gases that are byproducts of the digestion process of mammals and other animals. The medical term for the mixture of gases is flatus, informally known as a fart, or simply gas...
. According to the (unaired) pilot, he cannot process corn either. Leonard also wears glasses because of myopia
Myopia
Myopia , "shortsightedness" ) is a refractive defect of the eye in which collimated light produces image focus in front of the retina under conditions of accommodation. In simpler terms, myopia is a condition of the eye where the light that comes in does not directly focus on the retina but in...
, and practically cannot see without them. On one occasion, when his glasses were broken at the movie theater, he had to surreptitiously return to his apartment and retrieve his backup glasses. In order to avoid detection by a sick Sheldon and Penny, who was nursing him, Howard
Howard Wolowitz
Howard Joel Wolowitz, M.Eng is a fictional character on the CBS television series The Big Bang Theory, portrayed by actor Simon Helberg.Among the main male characters in the show, Howard is distinguished for lacking a doctoral degree, for still living with his mother, and for believing himself to...
and Raj
Rajesh Koothrappali
Rajesh Ramayan "Raj" Koothrappali, Ph.D. is a fictional character on the CBS television series The Big Bang Theory, portrayed by actor Kunal Nayyar....
helped him to navigate through the living room by using a helmet camera
Helmet camera
A helmet camera, otherwise known as a micro video camera, bullet camera, or lipstick camera, is a camera attached to a helmet allowing someone to make a visual record from their point of view , while keeping their hands and vision free....
. Leonard states in one episode that he suffers from sleep apnea
Sleep apnea
Sleep apnea is a sleep disorder characterized by abnormal pauses in breathing or instances of abnormally low breathing, during sleep. Each pause in breathing, called an apnea, can last from a few seconds to minutes, and may occur 5 to 30 times or more an hour. Similarly, each abnormally low...
. During his relationship with Leslie Winkle, he tells her that many members of his family have died from heart disease and thus he has a genetic disposition to the condition.
At various points in the show, Sheldon also says that Leonard gets carsick unless he sits in the front seat.
Family
All of the members of Leonard's family are accomplished scientists, except for his brother, who is a tenured law professor at Harvard Law SchoolHarvard Law School
Harvard Law School is one of the professional graduate schools of Harvard University. Located in Cambridge, Massachusetts, it is the oldest continually-operating law school in the United States and is home to the largest academic law library in the world. The school is routinely ranked by the U.S...
.
Leonard's mother, Dr. Beverly Hofstadter, is a psychiatrist
Psychiatrist
A psychiatrist is a physician who specializes in the diagnosis and treatment of mental disorders. All psychiatrists are trained in diagnostic evaluation and in psychotherapy...
and neuroscientist
Neuroscientist
A neuroscientist is an individual who studies the scientific field of neuroscience or any of its related sub-fields...
. She has a personality almost identical to Sheldon's, including strict speech patterns, lack of social conventions, and attention to detail, and is principally responsible for Leonard's difficult childhood. Due to his mother's views, Leonard never celebrated his birthday
Birthday
A birthday is a day or anniversary where a person celebrates his or her date of birth. Birthdays are celebrated in numerous cultures, often with a gift, party or rite of passage. Although the major religions celebrate the birth of their founders , Christmas – which is celebrated widely by...
when he was a child, and when she visited him she was not impressed with his unoriginal research. Leonard revealed to Penny that when he was young he built a "hugging machine" in order to compensate for the lack of affection from his mother. He further stated that his father used to borrow it. Beverly also belittles Leonard by pointing out that his brother and sister are more successful in their respective fields than he is. Leonard's brother, Michael, is a Harvard law professor and is engaged to the youngest appellate court judge in New Jersey
New Jersey
New Jersey is a state in the Northeastern and Middle Atlantic regions of the United States. , its population was 8,791,894. It is bordered on the north and east by the state of New York, on the southeast and south by the Atlantic Ocean, on the west by Pennsylvania and on the southwest by Delaware...
history, and his sister is a cutting-edge medical researcher working with gibbon
Gibbon
Gibbons are apes in the family Hylobatidae . The family is divided into four genera based on their diploid chromosome number: Hylobates , Hoolock , Nomascus , and Symphalangus . The extinct Bunopithecus sericus is a gibbon or gibbon-like ape which, until recently, was thought to be closely related...
s to cure diabetes.
Leonard's father is briefly mentioned as an anthropologist. Sheldon reveals that Leonard's middle name, "Leakey", comes from famed archaeologist Louis Leakey
Louis Leakey
Louis Seymour Bazett Leakey was a British archaeologist and naturalist whose work was important in establishing human evolutionary development in Africa. He also played a major role in creating organizations for future research in Africa and for protecting wildlife there...
, with whom Leonard's father had worked. Leonard is embarrassed by this middle name and its humorous connotations, and rarely mentions it.
Though little is known about Leonard's extended family, a few references to it have been made. In the first episode, Sheldon and Leonard discuss Leonard's grandmother, who had visited them on Thanksgiving
Thanksgiving (United States)
Thanksgiving, or Thanksgiving Day, is a holiday celebrated in the United States on the fourth Thursday in November. It has officially been an annual tradition since 1863, when, during the Civil War, President Abraham Lincoln proclaimed a national day of thanksgiving to be celebrated on Thursday,...
the year before. She has Alzheimer's disease
Alzheimer's disease
Alzheimer's disease also known in medical literature as Alzheimer disease is the most common form of dementia. There is no cure for the disease, which worsens as it progresses, and eventually leads to death...
and apparently "had an episode" during her visit, which resulted in her stripping off her clothes and carving the turkey. On Beverly's first visit, she tells Leonard that his uncle Floyd has died, which greatly upsets him (according to him, Floyd was the only family member he really liked). Leonard also has several other uncles, which Sheldon says are all very bald, and when they gather together, they look "like a half carton of eggs". Leonard describes his aunt, however, as being "one of the hairiest women you will ever meet".
Work
Leonard has an IQIntelligence quotient
An intelligence quotient, or IQ, is a score derived from one of several different standardized tests designed to assess intelligence. When modern IQ tests are constructed, the mean score within an age group is set to 100 and the standard deviation to 15...
of 173, and was 24 years old when he received his Ph.D
Doctorate
A doctorate is an academic degree or professional degree that in most countries refers to a class of degrees which qualify the holder to teach in a specific field, A doctorate is an academic degree or professional degree that in most countries refers to a class of degrees which qualify the holder...
from Princeton University
Princeton University
Princeton University is a private research university located in Princeton, New Jersey, United States. The school is one of the eight universities of the Ivy League, and is one of the nine Colonial Colleges founded before the American Revolution....
. Dr. Hofstadter received a dissertation of the year award for his doctoral paper on experimental particle physics
Particle physics
Particle physics is a branch of physics that studies the existence and interactions of particles that are the constituents of what is usually referred to as matter or radiation. In current understanding, particles are excitations of quantum fields and interact following their dynamics...
.
Leonard's work as an experimental physicist often includes the use of laser
Laser
A laser is a device that emits light through a process of optical amplification based on the stimulated emission of photons. The term "laser" originated as an acronym for Light Amplification by Stimulated Emission of Radiation...
s, such as a helium-neon laser
Helium-neon laser
A helium–neon laser or HeNe laser, is a type of gas laser whose gain medium consists of a mixture of helium and neon inside of a small bore capillary tube, usually excited by a DC electrical discharge.- History of HeNe laser development:...
or free-electron laser, and his research topics have varied from Bose-Einstein condensates and foundations of quantum mechanics
Quantum mechanics
Quantum mechanics, also known as quantum physics or quantum theory, is a branch of physics providing a mathematical description of much of the dual particle-like and wave-like behavior and interactions of energy and matter. It departs from classical mechanics primarily at the atomic and subatomic...
to soft cosmic ray
Cosmic ray
Cosmic rays are energetic charged subatomic particles, originating from outer space. They may produce secondary particles that penetrate the Earth's atmosphere and surface. The term ray is historical as cosmic rays were thought to be electromagnetic radiation...
s at sea level and development of novel rocket propellants. Leonard designs experiments in order to prove theories but, according to the cynical and egotistical theorist Sheldon
Sheldon Cooper
Sheldon Lee Cooper, B.S., M.S., M.A., Ph.D., Sc.D. is a fictional character from Texas on the CBS television series The Big Bang Theory, portrayed by actor Jim Parsons...
, his work is mostly derivative and thus unimportant.
His miscalculations in loading the top secret propellant for Howard's rocket led to the elevator in the apartment building where he lives being out of service for several years and his attempts to disprove the existence of dark matter
Dark matter
In astronomy and cosmology, dark matter is matter that neither emits nor scatters light or other electromagnetic radiation, and so cannot be directly detected via optical or radio astronomy...
were made moot by the work of another physicist. Yet, he resolved the latter by helping to solidify proof of the hypothetical matter's existence with a photomultiplier
Photomultiplier
Photomultiplier tubes , members of the class of vacuum tubes, and more specifically phototubes, are extremely sensitive detectors of light in the ultraviolet, visible, and near-infrared ranges of the electromagnetic spectrum...
, was invited as keynote speaker to a topical conference by the Institute of Experimental Physics for his successful research on supersolid
Supersolid
A supersolid is a spatially ordered material with superfluid properties. Superfluidity is a special quantum state of matter in which a substance flows with zero viscosity.-Background:...
s and has showed diverse knowledge of theoretical physics
Theoretical physics
Theoretical physics is a branch of physics which employs mathematical models and abstractions of physics to rationalize, explain and predict natural phenomena...
.
Relationships
Leonard was attracted to PennyPenny (The Big Bang Theory)
Penny is a fictional character on the CBS television series The Big Bang Theory, portrayed by American actress Kaley Cuoco.Penny is the main female character on the show. She is Leonard Hofstadter and Sheldon Cooper's neighbor across the hallway, and the main love interest of Leonard...
within seconds of spotting her. His infatuation with Penny becomes the major force that drives the series during the first seasons. By the end of the first season
Season finale
A season finale is the final episode of a season of a television program...
, Leonard finally managed to ask Penny out, and they had their first date. Subsequently, they broke up because Penny felt she wasn't as smart as Leonard would like.
Besides Penny, Leonard has been involved with only a few other women. One of Leonard's former girlfriends that is mentioned in several occasions is Joyce Kim. Although she has only recently appeared in person, Leonard's friends recalled on many occasions that they were together for only 27 days, after which Joyce, later revealed to be a spy
Espionage
Espionage or spying involves an individual obtaining information that is considered secret or confidential without the permission of the holder of the information. Espionage is inherently clandestine, lest the legitimate holder of the information change plans or take other countermeasures once it...
, defected to North Korea
North Korea
The Democratic People’s Republic of Korea , , is a country in East Asia, occupying the northern half of the Korean Peninsula. Its capital and largest city is Pyongyang. The Korean Demilitarized Zone serves as the buffer zone between North Korea and South Korea...
.
Initially, after feeling that Penny was not for him, Leonard turned his attention to fellow scientist Leslie Winkle. The first time Leonard asked Leslie out, she rejected him, and his further relationships with her proved to be only short-lived casual sex
Casual sex
Casual sex or hooking up refers to certain types of human sexual activity outside the context of a romantic relationship. The term is not always used consistently: some use it to refer to any extramarital sex, some use it to refer to sex in a casual relationship, whereas others reserve its use for...
encounters at her whim.
In the second season, Leonard began a stable relationship with Dr. Stephanie Barnett. Although the relationship went well, even earning Sheldon's approval, Leonard felt uncomfortable with Stephanie moving in with him, and the relationship was ended off-screen.
On another occasion, when Leonard's mother was visiting, he and Penny came very close to having sex
Sexual intercourse
Sexual intercourse, also known as copulation or coitus, commonly refers to the act in which a male's penis enters a female's vagina for the purposes of sexual pleasure or reproduction. The entities may be of opposite sexes, or they may be hermaphroditic, as is the case with snails...
, but Leonard ruined the moment by talking about their childhood issues with his mother and her father, respectively. In the second season finale, when Leonard, Sheldon, Howard, and Raj were due to leave for a three-month scientific expedition to the North Pole
North Pole
The North Pole, also known as the Geographic North Pole or Terrestrial North Pole, is, subject to the caveats explained below, defined as the point in the northern hemisphere where the Earth's axis of rotation meets its surface...
, Penny finally showed interest in Leonard, but kept her feelings a secret from him.
In the third season premiere
Premiere
A premiere is generally "a first performance". This can refer to plays, films, television programs, operas, symphonies, ballets and so on. Premieres for theatrical, musical and other cultural presentations can become extravagant affairs, attracting large numbers of socialites and much media...
, Leonard and Penny finally started a romantic relationship and had sex for the first time.
However, the relationship ended after Leonard prematurely told Penny he loved her and she realized she could not yet reciprocate. In order to win a bowling
Bowling
Bowling Bowling Bowling (1375–1425; late Middle English bowle, variant of boule Bowling (1375–1425; late Middle English bowle, variant of boule...
match against Sheldon's team, which included Leonard and Penny, Wil Wheaton picked up on the tension between Penny and Leonard and manipulated her into dumping him to break up the team. Shortly after the breakup, Leonard has a one-night stand
One-night stand
Originally, a one-night stand was a single theatre performance, usually by a guest performer on tour, as opposed to an ongoing engagement. Today, however, the term is more commonly defined as a single sexual encounter, in which neither participant has any intention or expectation of a relationship...
with a physicist he admires when she stays with him on a short visit, causing anger and open disgust from Penny. Leonard and Penny later resolve their feelings and their friendship continues.
In the third season finale, after Penny's failed attempts to move on from her relationship with Leonard, she gets drunk and has sex with him. In the morning, Leonard believes that their relationship has resumed, though Penny tells him that having sex with him was a mistake. This causes a strain on their friendship; at the end of the episode, Leonard gets drunk and tries to have sex with her, prompting Penny to kick him out of her apartment.
Leonard also has an affair with Raj's younger sister Priya (apparently every time she comes to town), despite a pinky swear with Howard that neither of them would attempt to make a move on her, and Raj giving his strong disapproval.
When Penny's father Wyatt comes to town, she pretends she is still with Leonard so as not to disappoint her father. Her father had apparently been extremely glad to learn she was finally dating a man who was not an idiot (according to his mindset). When he discovers the ruse, he begs Leonard not to give up on Penny.
Throughout the fourth season, it becomes obvious that Penny is still in love with Leonard. It is unclear whether or not Leonard has noticed this, though he clearly is still interested in Penny. In "The Benefactor Factor", a woman propositions Leonard in exchange for a large donation to the physics department; he initially resists and she admits that she planned to make the donation anyway, after which they engage in a one-night stand. Leonard arrives home the next morning, whereupon Penny recognizes his "walk of shame" and Sheldon thinks Leonard has a future in becoming a gigolo
Gigolo
Gigolo may refer to:* A male prostitute, escort, or dancer, who offers services to women* Gigolo , a 2006 single by Helena Paparizou* Gigolo , a 2003 single by Nick Cannon...
to rich ladies in exchange for donations.
When Priya returns, she and Leonard begin a relationship. Raj strongly opposes this, and Penny is secretly uncomfortable with Leonard dating someone else, eventually breaking down and crying while talking with her friend Amy Farrah Fowler. Once again, Leonard is unaware of Penny's true feelings. More recently, Priya pressures Leonard into telling Penny to leave him alone, which he does, albeit extremely reluctantly. Penny complies, though it is clear that she does not want Leonard out of her life. Penny eventually figures out how to stay in Leonard's life: by buddying up to Priya, which actually works.
In the Season 4 finale, Leonard runs into Penny and Raj as they come out of his room in the morning, just after Leonard and Priya appear to break up upon Leonard's learning that Priya is soon moving back to India
India
India , officially the Republic of India , is a country in South Asia. It is the seventh-largest country by geographical area, the second-most populous country with over 1.2 billion people, and the most populous democracy in the world...
. At the start of Season 5, Leonard and Priya are trying to maintain a long-distance relationship via Skype
Skype
Skype is a software application that allows users to make voice and video calls and chat over the Internet. Calls to other users within the Skype service are free, while calls to both traditional landline telephones and mobile phones can be made for a fee using a debit-based user account system...
(including a failed attempt at cybersex
Cybersex
Cybersex, also called computer sex, Internet sex, netsex, mudsex, TinySex and, colloquially, cybering, is a virtual sex encounter in which two or more persons connected remotely via computer network send each other sexually explicit messages describing a sexual experience...
) with Priya continuing to treat Leonard like a submissive partner. Despite being the most eager to have sex, Leonard proves here he is extremely awkward in these situations. Leonard later goes to a wedding with Amy, and they seem to take a liking to each other, though Sheldon disapproves, karate-chopping Leonard and saying, "She's not for you...not for you!". Later, despite feeling that he and Priya were in love and might get married, Leonard finds himself attracted to a comic book artist named Alice. The attraction is mutual, and they even share a kiss. Right when they are about to have sex, however, he tells Alice that he has a girlfriend, thus ending the relationship. Leonard then decides to confess his behavior to Priya on Skype, but he is shocked to learn that Priya has also cheated on him, sleeping with her ex-boyfriend. In the next episode, Leonard tells Sheldon that he is single, implying that he and Priya have broken up.