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Thursday, June 19, 2025

Neurosurgery

From Wikipedia, the free encyclopedia

Stereotactic guided insertion of DBS electrodes in neurosurgery
Occupation
Activity sectors
Surgery
Description
Education required

or

or

Fields of
employment
Hospitals, clinics

Neurosurgery or neurological surgery, known in common parlance as brain surgery, is the medical specialty that focuses on the surgical treatment or rehabilitation of disorders which affect any portion of the nervous system including the brain, spinal cord, peripheral nervous system, and cerebrovascular system. Neurosurgery as a medical specialty also includes non-surgical management of some neurological conditions.

Education and context

In different countries, there are different requirements for an individual to legally practice neurosurgery, and there are varying methods through which they must be educated. In most countries, neurosurgeon training requires a minimum period of seven years after graduating from medical school.

United Kingdom

In the United Kingdom, students must gain entry into medical school. The MBBS qualification (Bachelor of Medicine, Bachelor of Surgery) takes four to six years depending on the student's route. The newly qualified physician must then complete foundation training lasting two years; this is a paid training program in a hospital or clinical setting covering a range of medical specialties including surgery. Junior doctors then apply to enter the neurosurgical pathway. Unlike most other surgical specialties, it currently has its own independent training pathway which takes around eight years (ST1-8); before being able to sit for consultant exams with sufficient amounts of experience and practice behind them. Neurosurgery remains consistently amongst the most competitive medical specialties in which to obtain entry.

United States

In the United States, a neurosurgeon must generally complete four years of undergraduate education, four years of medical school, and seven years of residency (PGY-1-7).[4] Most, but not all, residency programs have some component of basic science or clinical research. Neurosurgeons may pursue additional training in the form of a fellowship after residency, or, in some cases, as a senior resident in the form of an enfolded fellowship. These fellowships include pediatric neurosurgery, trauma/neurocritical care, functional and stereotactic surgery, surgical neuro-oncology, radiosurgery, neurovascular surgery, skull-base surgery, peripheral nerve and complex spinal surgery. Fellowships typically span one to two years. In the U.S., neurosurgery is a very small, highly competitive specialty, constituting only 0.5 percent of all physicians.

History

Neurosurgery, or the premeditated incision into the head for pain relief, has been around for thousands of years, but notable advancements in neurosurgery have only come within the last hundred years.

Trepanned skull from Edinburgh

Ancient

The Incas appear to have practiced a procedure known as trepanation since before European colonization. During the Middle Ages in Al-Andalus from 936 to 1013 AD, Al-Zahrawi performed surgical treatments of head injuries, skull fractures, spinal injuries, hydrocephalus, subdural effusions and headache. During the Roman Empire, doctors and surgeons performed neurosurgery on depressed skull fractures. Simple forms of neurosurgery were performed on King Henri II in 1559, after a jousting accident with Gabriel Montgomery fatally wounded him. Ambroise Paré and Andreas Vesalius, both experts in their field at the time, attempted their own methods, to no avail, in curing Henri. In China, Hua Tuo created the first general anaesthesia called mafeisan, which he used on surgical procedures on the brain.

Modern

History of tumor removal: In 1879, after locating it via neurological signs alone, Scottish surgeon William Macewen (1848–1924) performed the first successful brain tumor removal. On November 25, 1884, after English physician Alexander Hughes Bennett (1848–1901) used Macewen's technique to locate it, English surgeon Rickman Godlee (1849–1925) performed the first primary brain tumor removal, which differs from Macewen's operation in that Bennett operated on the exposed brain, whereas Macewen operated outside of the "brain proper" via trepanation. On March 16, 1907, Austrian surgeon Hermann Schloffer became the first to successfully remove a pituitary tumor.

Lobotomy: also known as leucotomy, was a form of psychosurgery, a neurosurgical treatment of mental disorders that involves severing connections in the brain's prefrontal cortex. The originator of the procedure, Portuguese neurologist António Egas Moniz, shared the Nobel Prize for Physiology or Medicine of 1949. Some patients improved in some ways after the operation, but complications and impairments – sometimes severe – were frequent. The procedure was controversial from its initial use, in part due to the balance between benefits and risks. It is mostly rejected as a treatment now and non-compliant with patients' rights.

History of electrodes in the brain: In 1878, Richard Caton discovered that electrical signals transmitted through an animal's brain. In 1950 Jose Delgado invented the first electrode that was implanted in an animal's brain (bull), using it to make it run and change direction. In 1972 the cochlear implant, a neurological prosthetic that allowed deaf people to hear was marketed for commercial use. In 1998 researcher Philip Kennedy implanted the first Brain Computer Interface (BCI) into a human subject.

A survey done in 2010 on 100 most cited works in neurosurgery shows that the works mainly cover clinical trials evaluating surgical and medical therapies, descriptions of novel techniques in neurosurgery, and descriptions of systems classifying and grading diseases.

Modern surgical instruments

The main advancements in neurosurgery came about as a result of highly crafted tools. Modern neurosurgical tools, or instruments, include chisels, curettes, dissectors, distractors, elevators, forceps, hooks, impactors, probes, suction tubes, power tools, and robots. Most of these modern tools have been in medical practice for a relatively long time. The main difference of these tools in neurosurgery, were the precision in which they were crafted. These tools are crafted with edges that are within a millimeter of desired accuracy. Other tools, such as handheld power saws and robots, have only recently been commonly used inside of a neurological operating room. As an example, the University of Utah developed a device for computer-aided design / computer-aided manufacturing (CAD-CAM) which uses an image-guided system to define a cutting tool path for a robotic cranial drill.

Organised neurosurgery

World Academy of Neurological Surgery's conference

The World Federation of Neurosurgical Societies (WFNS), founded in 1955, in Switzerland, as a professional, scientific, non governmental organization, is composed of 130 member societies: consisting of 5 Continental Associations (AANS, AASNS, CAANS, EANS and FLANC), 6 Affiliate Societies, and 119 National Neurosurgical Societies, representing some 50,000 neurosurgeons worldwide. It has a consultative status in the United Nations. The official Journal of the Organization is World Neurosurgery. The other global organisations being the World Academy of Neurological Surgery (WANS) and the World Federation of Skull Base Societies (WFSBS).

Main divisions

General neurosurgery involves most neurosurgical conditions including neuro-trauma and other neuro-emergencies such as intracranial hemorrhage. Most level 1 hospitals have this kind of practice.

Specialized branches have developed to cater to special and difficult conditions. These specialized branches co-exist with general neurosurgery in more sophisticated hospitals. To practice advanced specialization within neurosurgery, additional higher fellowship training of one to two years is expected from the neurosurgeon. Some of these divisions of neurosurgery are:

  1. Vascular neurosurgery includes clipping of aneurysms and performing carotid endarterectomy (CEA).
  2. Stereotactic neurosurgery, functional neurosurgery, and epilepsy surgery (the latter includes partial or total corpus callosotomy – severing part or all of the corpus callosum to stop or lessen seizure spread and activity, and the surgical removal of functional, physiological and/or anatomical pieces or divisions of the brain, called epileptic foci, that are operable and that are causing seizures, and also the more radical and rare partial or total lobectomy, or even hemispherectomy – the removal of part or all of one of the lobes, or one of the cerebral hemispheres of the brain; those two procedures, when possible, are also very, very rarely used in oncological neurosurgery or to treat very severe neurological trauma, such as stab or gunshot wounds to the brain)
  3. Oncological neurosurgery also called neurosurgical oncology; includes pediatric oncological neurosurgery; treatment of benign and malignant central and peripheral nervous system cancers and pre-cancerous lesions in adults and children (including, among others, glioblastoma multiforme and other gliomas, brain stem cancer, astrocytoma, pontine glioma, medulloblastoma, spinal cancer, tumors of the meninges and intracranial spaces, secondary metastases to the brain, spine, and nerves, and peripheral nervous system tumors)
  4. Skull base surgery
  5. Spinal neurosurgery
  6. Peripheral nerve surgery
  7. Pediatric neurosurgery (for cancer, seizures, bleeding, stroke, cognitive disorders or congenital neurological disorders)

Commonly performed surgeries

According to an analysis by the American College of Surgeons National Surgical Quality Improvement Program (NSQIP), the most common surgeries performed by neurosurgeons in between 2006 and 2014 were the following:

Neuropathology

Histopathology specimen of Angiocentric glioma, higher magnification, HE stain

Neuropathology is a specialty within the study of pathology focused on the disease of the brain, spinal cord, and neural tissue. This includes the central nervous system and the peripheral nervous system. Tissue analysis comes from either surgical biopsies or post mortem autopsies. Common tissue samples include muscle fibers and nervous tissue. Common applications of neuropathology include studying samples of tissue in patients who have Parkinson's disease, Alzheimer's disease, dementia, Huntington's disease, amyotrophic lateral sclerosis, mitochondria disease, and any disorder that has neural deterioration in the brain or spinal cord.

History

While pathology has been studied for millennia only within the last few hundred years has medicine focused on a tissue- and organ-based approach to tissue disease. In 1810, Thomas Hodgkin started to look at the damaged tissue for the cause. This was conjoined with the emergence of microscopy and started the current understanding of how the tissue of the human body is studied.

Neuroanesthesia

Neuroanesthesia is a field of anesthesiology which focuses on neurosurgery. Anesthesia is not used during the middle of an "awake" brain surgery. Awake brain surgery is where the patient is conscious for the middle of the procedure and sedated for the beginning and end. This procedure is used when the tumor does not have clear boundaries and the surgeon wants to know if they are invading on critical regions of the brain which involve functions like talking, cognition, vision, and hearing. It will also be conducted for procedures which the surgeon is trying to combat epileptic seizures.

History

The physician Hippocrates (460–370 BCE) made accounts of using different wines to sedate patients while trepanning. In 60 CE, Dioscorides, a physician, pharmacologist, and botanist, detailed how mandrake, henbane, opium, and alcohol were used to put patients to sleep during trepanning. In 972 CE, two brother surgeons in Paramara, now India, used "samohine" to sedate a patient while removing a small tumor, and awoke the patient by pouring onion and vinegar in the patient's mouth. The combination of carbon dioxide, hydrogen, and nitrogen, was a form of neuroanesthesia adopted in the 18th century and introduced by Humphry Davy.

Neurosurgery methods

Various Imaging methods are used in modern neurosurgery diagnosis and treatment. They include computer assisted imaging computed tomography (CT), magnetic resonance imaging (MRI), positron emission tomography (PET), magnetoencephalography (MEG), and stereotactic radiosurgery. Some neurosurgery procedures involve the use of intra-operative MRI and functional MRI.

In conventional neurosurgery the neurosurgeon opens the skull, creating a large opening to access the brain. Techniques involving smaller openings with the aid of microscopes and endoscopes are now being used as well. Methods that utilize small craniotomies in conjunction with high-clarity microscopic visualization of neural tissue offer excellent results. However, the open methods are still traditionally used in trauma or emergency situations.

Microsurgery is utilized in many aspects of neurological surgery. Microvascular techniques are used in EC-IC bypass surgery and in restoration carotid endarterectomy. The clipping of an aneurysm is performed under microscopic vision. Minimally-invasive spine surgery utilizes microscopes or endoscopes. Procedures such as microdiscectomy, laminectomy, and artificial disc replacement rely on microsurgery.

Using stereotaxy neurosurgeons can approach a minute target in the brain through a minimal opening. This is used in functional neurosurgery where electrodes are implanted or gene therapy is instituted with high level of accuracy as in the case of Parkinson's disease or Alzheimer's disease. Using the combination method of open and stereotactic surgery, intraventricular hemorrhages can potentially be evacuated successfully. Conventional surgery using image guidance technologies is also becoming common and is referred to as surgical navigation, computer-assisted surgery, navigated surgery, stereotactic navigation. Similar to a car or mobile Global Positioning System (GPS), image-guided surgery systems, like Curve Image Guided Surgery and StealthStation, use cameras or electromagnetic fields to capture and relay the patient's anatomy and the surgeon's precise movements in relation to the patient, to computer monitors in the operating room. These sophisticated computerized systems are used before and during surgery to help orient the surgeon with three-dimensional images of the patient's anatomy including the tumor. Real-time functional brain mapping has been employed to identify specific functional regions using electrocorticography (ECoG)

Minimally invasive endoscopic surgery is commonly utilized by neurosurgeons when appropriate. Techniques such as endoscopic endonasal surgery are used in pituitary tumors, craniopharyngiomas, chordomas, and the repair of cerebrospinal fluid leaks. Ventricular endoscopy is used in the treatment of intraventricular bleeds, hydrocephalus, colloid cyst and neurocysticercosis. Endonasal endoscopy is at times carried out with neurosurgeons and ENT surgeons working together as a team.

Repair of craniofacial disorders and disturbance of cerebrospinal fluid circulation is done by neurosurgeons who also occasionally team up with maxillofacial and plastic surgeons. Cranioplasty for craniosynostosis is performed by pediatric neurosurgeons with or without plastic surgeons.

Neurosurgeons are involved in stereotactic radiosurgery along with radiation oncologists in tumor and AVM treatment. Radiosurgical methods such as Gamma knife, Cyberknife and Novalis Radiosurgery are used as well.

Endovascular neurosurgery utilize endovascular image guided procedures for the treatment of aneurysms, AVMs, carotid stenosis, strokes, and spinal malformations, and vasospasms. Techniques such as angioplasty, stenting, clot retrieval, embolization, and diagnostic angiography are endovascular procedures.

A common procedure performed in neurosurgery is the placement of ventriculo-peritoneal shunt (VP shunt). In pediatric practice this is often implemented in cases of congenital hydrocephalus. The most common indication for this procedure in adults is normal pressure hydrocephalus (NPH).

Neurosurgery of the spine covers the cervical, thoracic and lumbar spine. Some indications for spine surgery include spinal cord compression resulting from trauma, arthritis of the spinal discs, or spondylosis. In cervical cord compression, patients may have difficulty with gait, balance issues, and/or numbness and tingling in the hands or feet. Spondylosis is the condition of spinal disc degeneration and arthritis that may compress the spinal canal. This condition can often result in bone-spurring and disc herniation. Power drills and special instruments are often used to correct any compression problems of the spinal canal. Disc herniations of spinal vertebral discs are removed with special rongeurs. This procedure is known as a discectomy. Generally once a disc is removed it is replaced by an implant which will create a bony fusion between vertebral bodies above and below. Instead, a mobile disc could be implanted into the disc space to maintain mobility. This is commonly used in cervical disc surgery. At times instead of disc removal a Laser discectomy could be used to decompress a nerve root. This method is mainly used for lumbar discs. Laminectomy is the removal of the lamina of the vertebrae of the spine in order to make room for the compressed nerve tissue.

Surgery for chronic pain is a sub-branch of functional neurosurgery. Some of the techniques include implantation of deep brain stimulators, spinal cord stimulators, peripheral stimulators and pain pumps.

Surgery of the peripheral nervous system is also possible, and includes the very common procedures of carpal tunnel decompression and peripheral nerve transposition. Numerous other types of nerve entrapment conditions and other problems with the peripheral nervous system are treated as well.

Conditions

Conditions treated by neurosurgeons include, but are not limited to:

Recovery

Postoperative pain

Pain following brain surgery can be significant and may lengthen recovery, increase the amount of time a person stays in the hospital following surgery, and increase the risk of complications following surgery. Severe acute pain following brain surgery may also increase the risk of a person developing a chronic post-craniotomy headache. Approaches to treating pain in adults include treatment with nonsteroidal anti‐inflammatory drugs (NSAIDs), which have been shown to reduce pain for up to 24 hours following surgery. Low-quality evidence supports the use of the medications dexmedetomidine, pregabalin or gabapentin to reduce post-operative pain. Low-quality evidence also supports scalp blocks and scalp infiltration to reduce postoperative pain. Gabapentin or pregabalin may also decrease vomiting and nausea following surgery, based on very low-quality medical evidence.

Notable neurosurgeons

  • Ludvig Puusepp – known as one of the founding fathers of modern neurosurgery, world's first professor of neurosurgery.
  • Joseph Ransohoff – known for his pioneering use of medical imaging and catheterization in neurosurgery, and for founding the first neurosurgery intensive care unit.
  • Majid Samii – pioneer of cerebello-pontine angle tumor surgery. World Federation of Neurosurgical Societies coined a medal of honor bearing Samii's name which would be given to outstanding neurosurgeons every two years.
  • Juliet Sekabunga Nalwanga – Uganda's first woman neurosurgeon.
  • Robert Wheeler Rand – among the first to introduce the surgical microscope into neurosurgical procedures in 1957 and published first textbook on Microneurosurgery in 1969.
  • Robert J. White – Established the Vatican's Commission on Biomedical Ethics in 1981 after his appointment to the Pontifical Academy of Sciences and was famous for his head transplants on living monkeys.
  • Gazi Yaşargil – known as the father of microneurosurgery.

Bioethics in neurosurgery

Neurosurgery is a part of practical medicine and the only specialty that involves invasive intervention in the activity of the living brain. The brain ensures the structural and functional integrity of the body and the implementation of all the main life processes of the body. Therefore, neurosurgery faces a wide range of bioethical issues and a significant selection of the latest treatment technologies.

Neurosurgery has the following applied scientific and ethical problems:

AllTrials

From Wikipedia, the free encyclopedia
https://en.wikipedia.org/wiki/AllTrials
an office folder showing the AllTrials wordmark

AllTrials (sometimes called All Trials or AllTrials.net) is a project advocating that clinical research adopt the principles of open research. The project summarizes itself as "All trials registered, all results reported": that is, all clinical trials should be listed in a clinical trials registry, and their results should always be shared as open data.

At the center of the organisation is a petition signed by over 85,000 individuals and 599 organisations (as of August 2015):

Thousands of clinical trials have not reported their results; some have not even been registered.

Information on what was done and what was found in these trials could be lost forever to doctors and researchers, leading to bad treatment decisions, missed opportunities for good medicine, and trials being repeated.

All trials past and present should be registered, and the full methods and the results reported.

We call on governments, regulators and research bodies to implement measures to achieve this.

Ben Goldacre, author of Bad Science and Bad Pharma, is a founder of the campaign and its most public spokesperson. In 2016, he participated in the launch of the OpenTrials database.

AllTrials is an international initiative of Bad Science, BMJ, Centre for Evidence-based Medicine, Cochrane Collaboration, James Lind Initiative, PLOS and Sense about Science and is being led in the US by Sense about Science USA, Dartmouth's Geisel School of Medicine and the Dartmouth Institute for Health Policy & Clinical Practice.

Issues addressed

The project is a reaction to under-reporting of research.

A substantial proportion (estimates range from one-third to one-half) of medical research goes unpublished. It has also been shown that negative findings are less likely to be published than positive ones, even in the absence of conflicts of interest.

Much medical research is done by the pharmaceutical industry, which have a conflict of interest reporting results which may hurt sales of their products. There is a measurable funding bias in reporting; studies have shown that published drug studies funded by pharmaceutical companies are much more likely to support the use of the tested drug than studies with other funding. Industry-funded trials are also less likely to be published.

If the statistical methods used to analyse the trial are not chosen before the study it started, there is a danger that researchers will intentionally or unintentionally pick the method that gives the results they expect, or which gives the most significant results. This makes the analysis statistically invalid.

Not publishing trials which fail to find a clear effect exposes trial volunteers to pointless risk and wastes research effort (as the same trial is repeated over and over). It also biases the medical literature, making it report effects where none exist (since, given enough trials, eventually one will find a difference by pure chance).

Pre-trial registration makes non-publication and changes in analysis methods obvious to medical reviewers. It also enables authors of meta-studies to track down and analyse missing data. Finally, it lets doctors and patients know when a trial is looking for volunteers.

There are other sources of bias, such as the conditions sometimes attached to funding by funding agencies with a financial interest in the trial's outcome. Medical researchers may be asked to agree to allow the funding agency to censor results. Some funding agencies may also refuse to give the medical researcher access to the raw data, giving them only the finished analysis, or even a draft paper, and asking them to put their name to it. This is not acceptable academic practice, and some academic journals require that authors sign a statement that they have not entered into such agreements.

Ben Goldacre, a physician and spokesperson for the campaign, would like to address the systematic flaws in clinical research which cause data to be lost after it is gathered.

Coverage

The campaign has been widely covered, and supported, in the academic press. The British Medical Journal and PLOS are founding members. Nature and The Lancet both published supportive articles in January 2014.

There has also been mainstream media coverage.

Controversy

There has been criticism from the Pharmaceutical Research and Manufacturers of America (PhRMA), with senior vice-president Matt Bennett saying that trial data disclosure measures which AllTrials has recommended to the European Medicines Agency "could risk patient privacy, lead to fewer clinical trials, and result in fewer new medicines to meet patient needs and improve health.".

AllTrials have published a detailed statement of exactly what they want to see published, which states "The AllTrials campaign is not calling for individual patient data to be made publicly available".

A 2012 editorial published by senior regulators from the European Medicines agency largely agreed with AllTrials, saying "We consider it neither desirable nor realistic to maintain the status quo of limited availability of regulatory trials data". They were also of the opinion that adequate standards for protection of personal data could be written. However, they warned that third party reanalysis was neither a guarantee of quality nor of lack of conflict of interest, which, in the worst case, could lead to negative public health consequences.

They suggested that reanalyses should therefore be subject to the same regulations as sponsor analyses, such as registering analysis plans. They argued against completely unrestricted access to data, but in favor of broader access. AllTrials is not calling for completely unrestricted access to raw data, so the scope of disagreements is limited to what restrictions should be in place.

Supporters

The campaign is an initiative of Sense about ScienceCentre for Evidence Based Medicine, The Dartmouth Institute for Health Policy and Clinical PracticeJames Lind Alliance, Cochrane CollaborationBMJ Group, PLOS, and Bad Science. The petition statement of AllTrials has been signed by organizations including Wellcome TrustBritish Library, Medical Research Council (UK), British Heart Foundation, Institute for Quality and Efficiency in Health Care, National Institute for Health and Care Excellence, BioMed CentralNational Physicians Alliance, Royal Society of Medicine, Health Research Authority, American Medical Student Association, GlaxoSmithKline, and others.

As of May 2017, The AllTrials petition has been signed by 90,282 people and 721 organisations. In October 2016, AllTrials published a road map detailing steps that various types of organisations can take to get more trials registered and more results reported.

85 investors with >€3.5 trillion (£2.45trn; $3.83trn) of investments have supported AllTrials (as of July 2015), with Peter van der Werf of RobecoSAM saying: "We deem this to be a financially material factor and encourage all companies to gain credibility regarding their approach to clinical trial transparency by signing up to the AllTrials principles.". The Laura and John Arnold Foundation provided early and ongoing financial support.

The original policy of the Coalition for Epidemic Preparedness Innovations required that funded parties pre-register any trials in a clinical trials registry, publish results within a year of study completion (except with compelling reason and permission of CEPI), publish results in open-access articles, and have mechanisms for securely sharing underlying data and results, including negative results, in a way that preserves trial volunteer privacy. In May 2018 the CEPI proposed changing the policy to remove these provisions. The policy was changed by the CEPI in December 2018.

Opponents

The European Federation of Pharmaceutical Industries and Associations and Pharmaceutical Research and Manufacturers of America have expressed interest in lobbying against the campaign. Campaign supporters criticized Hoffmann-La Roche's plans to be more open but not to the extent requested by AllTrials.

Experimental physics

From Wikipedia, the free encyclopedia

Experimental physics is the category of disciplines and sub-disciplines in the field of physics that are concerned with the observation of physical phenomena and experiments. Methods vary from discipline to discipline, from simple experiments and observations, such as experiments by Galileo Galilei, to more complicated ones, such as the Large Hadron Collider.

Overview

Sir Ernest Rutherford's laboratory, early 20th century

Experimental physics is a branch of physics that is concerned with data acquisition, data-acquisition methods, and the detailed conceptualization (beyond simple thought experiments) and realization of laboratory experiments. It is often contrasted with theoretical physics, which is more concerned with predicting and explaining the physical behaviour of nature than with acquiring empirical data.

Although experimental and theoretical physics are concerned with different aspects of nature, they both share the same goal of understanding it and have a symbiotic relationship. The former provides data about the universe, which can then be analyzed in order to be understood, while the latter provides explanations for the data and thus offers insight into how to better acquire data and set up experiments. Theoretical physics can also offer insight into what data is needed in order to gain a better understanding of the universe, and into what experiments to devise in order to obtain it.

The tension between experimental and theoretical aspects of physics was expressed by James Clerk Maxwell as "It is not till we attempt to bring the theoretical part of our training into contact with the practical that we begin to experience the full effect of what Faraday has called 'mental inertia' - not only the difficulty of recognizing, among the concrete objects before us, the abstract relation which we have learned from books, but the distracting pain of wrenching the mind away from the symbols to the objects, and from the objects back to the symbols. This however is the price we have to pay for new ideas."

History

As a distinct field, experimental physics was established in early modern Europe, during what is known as the Scientific Revolution, by physicists such as Galileo Galilei, Christiaan Huygens, Johannes Kepler, Blaise Pascal and Sir Isaac Newton. In the early 17th century, Galileo made extensive use of experimentation to validate physical theories, which is the key idea in the modern scientific method. Galileo formulated and successfully tested several results in dynamics, in particular the law of inertia, which later became the first law in Newton's laws of motion. In Galileo's Two New Sciences, a dialogue between the characters Simplicio and Salviati discuss the motion of a ship (as a moving frame) and how that ship's cargo is indifferent to its motion. Huygens used the motion of a boat along a Dutch canal to illustrate an early form of the conservation of momentum.

Experimental physics is considered to have reached a high point with the publication of the Philosophiae Naturalis Principia Mathematica in 1687 by Sir Isaac Newton (1643–1727). In 1687, Newton published the Principia, detailing two comprehensive and successful physical laws: Newton's laws of motion, from which arise classical mechanics; and Newton's law of universal gravitation, which describes the fundamental force of gravity. Both laws agreed well with experiment. The Principia also included several theories in fluid dynamics.

From the late 17th century onward, thermodynamics was developed by physicist and chemist Robert Boyle, Thomas Young, and many others. In 1733, Daniel Bernoulli used statistical arguments with classical mechanics to derive thermodynamic results, initiating the field of statistical mechanics. In 1798, Benjamin Thompson (Count Rumford) demonstrated the conversion of mechanical work into heat, and in 1847 James Prescott Joule stated the law of conservation of energy, in the form of heat as well as mechanical energy. Ludwig Boltzmann, in the nineteenth century, is responsible for the modern form of statistical mechanics.

Besides classical mechanics and thermodynamics, another great field of experimental inquiry within physics was the nature of electricity. Observations in the 17th and eighteenth century by scientists such as Boyle, Stephen Gray, and Benjamin Franklin created a foundation for later work. These observations also established our basic understanding of electrical charge and current. By 1808 John Dalton had discovered that atoms of different elements have different weights and proposed the modern theory of the atom.

It was Hans Christian Ørsted who first proposed the connection between electricity and magnetism after observing the deflection of a compass needle by a nearby electric current. By the early 1830s Michael Faraday had demonstrated that magnetic fields and electricity could generate each other. In 1864 James Clerk Maxwell presented to the Royal Society a set of equations that described this relationship between electricity and magnetism. Maxwell's equations also predicted correctly that light is an electromagnetic wave. Starting with astronomy, the principles of natural philosophy crystallized into fundamental laws of physics which were enunciated and improved in the succeeding centuries. By the 19th century, the sciences had segmented into multiple fields with specialized researchers and the field of physics, although logically pre-eminent, no longer could claim sole ownership of the entire field of scientific research.

Current experiments

A view of the CMS detector, an experimental endeavour of the LHC at CERN.

Some examples of prominent experimental physics projects are:

  • Relativistic Heavy Ion Collider which collides heavy ions such as gold ions (it is the first heavy ion collider) and protons, it is located at Brookhaven National Laboratory, on Long Island, USA.
  • HERA, which collides electrons or positrons and protons, and is part of DESY, located in Hamburg, Germany.
  • LHC, or the Large Hadron Collider, which completed construction in 2008 but suffered a series of setbacks. The LHC began operations in 2008, but was shut down for maintenance until the summer of 2009. It is the world's most energetic collider upon completion, it is located at CERN, on the French-Swiss border near Geneva. The collider became fully operational March 29, 2010 a year and a half later than originally planned.
  • LIGO, the Laser Interferometer Gravitational-Wave Observatory, is a large-scale physics experiment and observatory to detect cosmic gravitational waves and to develop gravitational-wave observations as an astronomical tool. Currently two LIGO observatories exist: LIGO Livingston Observatory in Livingston, Louisiana, and LIGO Hanford Observatory near Richland, Washington.
  • JWST, or the James Webb Space Telescope, launched in 2021. It will be the successor to the Hubble Space Telescope. It will survey the sky in the infrared region. The main goals of the JWST will be in order to understand the initial stages of the universe, galaxy formation as well as the formations of stars and planets, and the origins of life.
  • Mississippi State Axion Search (2016 completion), Light Shining Through a Wall Experiment (LSW); EM Source: .7m, 50W continuous radio wave emitter.

Method

Experimental physics uses two main methods of experimental research, controlled experiments, and natural experiments. Controlled experiments are often used in laboratories as laboratories can offer a controlled environment. Natural experiments are used, for example, in astrophysics when observing celestial objects where control of the variables in effect is impossible.

Famous experiments

Famous experiments include:

Experimental techniques

Some well-known experimental techniques include:

Prominent experimental physicists

Famous experimental physicists include:

Timelines

See the timelines below for listings of physics experiments.

Science of morality

From Wikipedia, the free encyclopedia

Science of morality (also known as science of ethics or scientific ethics) may refer to various forms of ethical naturalism grounding morality and ethics in rational, empirical consideration of the natural world. It is sometimes framed as using the scientific approach to determine what is right and wrong, in contrast to the widespread belief that "science has nothing to say on the subject of human values".

Overview

Moral science may refer to the consideration of what is best for, and how to maximize the flourishing of, either particular individuals or all conscious creatures. It has been proposed that "morality" can be appropriately defined on the basis of fundamental premises necessary for any empirical, secular, or philosophical discussion and that societies can use the methods of science to provide answers to moral questions.

The norms advocated by moral scientists (e.g. rights to abortion, euthanasia, and drug liberalization under certain circumstances) would be founded upon the shifting and growing collection of human understanding. Even with science's admitted degree of ignorance, and the various semantic issues, moral scientists can meaningfully discuss things as being almost certainly "better" or "worse" for promoting flourishing.

History

In philosophy

Utilitarian Jeremy Bentham discussed some of the ways moral investigations are a science. He criticized deontological ethics for failing to recognize that it needed to make the same presumptions as his science of morality to really work – whilst pursuing rules that were to be obeyed in every situation (something that worried Bentham).

W. V. O. Quine advocated naturalizing epistemology by looking to natural sciences like psychology for a full explanation of knowledge. His work contributed to a resurgence of moral naturalism in the last half of the 20th century. Paul Kurtz, who believes that the careful, secular pursuit of normative rules is vital to society, coined the term eupraxophy to refer to his approach to normative ethics. Steven Pinker, Sam Harris, and Peter Singer believe that we learn what is right and wrong through reason and empirical methodology.

Maria Ossowska used the methods of science to understand the origins of moral norms.

Maria Ossowska thought that sociology was inextricably related to philosophical reflections on morality, including normative ethics. She proposed that science analyse: (a) existing social norms and their history, (b) the psychology of morality, and the way that individuals interact with moral matters and prescriptions, and (c) the sociology of morality.

The theory and methods of a normative science of morality are explicitly discussed in Joseph Daleiden's The Science of Morality: The Individual, Community, and Future Generations (1998). Daleiden's book, in contrast to Harris, extensively discusses the relevant philosophical literature. In The Moral Landscape: How Science Can Determine Human Values, Sam Harris's goal is to show how moral truth can be backed by "science", or more specifically, empirical knowledge, critical thinking, philosophy, but most controversially, the scientific method.

Patricia Churchland offers that, accepting David Hume's is–ought problem, the use of induction from premises and definitions remains a valid way of reasoning in life and science:

Our moral behavior, while more complex than the social behavior of other animals, is similar in that it represents our attempt to manage well in the existing social ecology. ... from the perspective of neuroscience and brain evolution, the routine rejection of scientific approaches to moral behavior based on Hume's warning against deriving ought from is seems unfortunate, especially as the warning is limited to deductive inferences. ... The truth seems to be that values rooted in the circuitry for caring—for well-being of self, offspring, mates, kin, and others—shape social reasoning about many issues: conflict resolutions, keeping the peace, defense, trade, resource distribution, and many other aspects of social life in all its vast richness.

Daleiden and Leonard Carmichael warn that science is probabilistic, and that certainty is not possible. One should therefore expect that moral prescriptions will change as humans gain understanding.

In futurism

Transhumanist philosophers such as David Pearce and Mark Alan Walker have extensively discussed the ethical implications of future technologies. Walker coined the term "biohappiness" to describe the idea of directly manipulating the biological roots of happiness in order to increase it. Pearce argues that suffering could eventually be eradicated entirely, stating that: "It is predicted that the world's last unpleasant experience will be a precisely dateable event." Proposed technological methods of overcoming the hedonic treadmill include wireheading (direct brain stimulation for uniform bliss), which undermines motivation and evolutionary fitness; designer drugs, offering sustainable well-being without side effects, though impractical for lifelong reliance; and genetic engineering, the most promising approach. Genetic recalibration through hyperthymia-promoting genes could raise hedonic set-points, fostering adaptive well-being, creativity, and productivity while maintaining responsiveness to stimuli. While scientifically achievable, this transformation requires careful ethical and societal considerations to navigate its profound implications.

On the opposite end of the spectrum, risks of astronomical suffering are possible futures in which vastly more suffering will exist than has ever been produced on earth so far in all of earth's history. Possible sources of these risks include artificial superintelligence, genetic engineering for maximum suffering, space colonization, and terraforming leading to an increase in wild animal suffering.

Views in scientific morality

Training to promote good behaviour

The science of morality may aim to discover the best ways to motivate and shape individuals. Methods to accomplish this include instilling explicit virtues, building character strengths, and forming mental associations. These generally require some level of practical reason. James Rest suggested that abstract reasoning is also a factor in making moral judgements and emphasized that moral judgements alone do not predict moral behaviour: “Moral judgement may be closely related to advocacy behaviour, which in turn influences social institutions, which in turn creates a system of norms and sanctions that influences people’s behaviour.” Daleiden suggested that religions instill a practical sense of virtue and justice, right and wrong. They also effectively use art and myths to educate people about moral situations.

Role of government

Harris argues that moral science does not imply an "Orwellian future" with "scientists at every door". Instead, Harris imagines data about normative moral issues being shared in the same way as other sciences (e.g. peer-reviewed journals on medicine).

Daleiden specifies that government, like any organization, should have limited power. He says "centralization of power irrevocably in the hands of one person or an elite has always ultimately led to great evil for the human race. It was the novel experiment of democracy—a clear break with tradition—that ended the long tradition of tyranny.” He is also explicit that government should only use law to enforce the most basic, reasonable, proven and widely supported moral norms. In other words, there are a great many moral norms that should never be the task of the government to enforce.

Role of punishment

One author has argued that to attain a society where people are motivated by conditioned self-interest, punishment must go hand-in-hand with reward. For instance, in this line of reasoning, prison remains necessary for many perpetrators of crimes. This is so, even if libertarian free will is false. This is because punishment can still serve its purposes: it deters others from committing their own crimes, educates and reminds everyone about what the society stands for, incapacitates the criminal from doing more harm, goes some way to relieving or repaying the victim, and corrects the criminal (also see recidivism). This author argues that, at least, any prison system should be pursuing those goals, and that it is an empirical question as to what sorts of punishment realize these goals most effectively, and how well various prison systems actually serve these purposes.

Research

The brain areas that are consistently involved when humans reason about moral issues have been investigated. The neural network underlying moral decisions overlaps with the network pertaining to representing others' intentions (i.e., theory of mind) and the network pertaining to representing others' (vicariously experienced) emotional states (i.e., empathy). This supports the notion that moral reasoning is related to both seeing things from other persons’ points of view and to grasping others’ feelings. These results provide evidence that the neural network underlying moral decisions is probably domain-global (i.e., there might be no such things as a "moral module" in the human brain) and might be dissociable into cognitive and affective sub-systems.

An essential, shared component of moral judgment involves the capacity to detect morally salient content within a given social context. Recent research implicated the salience network in this initial detection of moral content. The salience network responds to behaviourally salient events, and may be critical to modulate downstream default and frontal control network interactions in the service of complex moral reasoning and decision-making processes. This suggest that moral cognition involves both bottom-up and top-down attentional processes, mediated by discrete large-scale brain networks and their interactions.

In universities

Moral sciences is offered at the degree level at Ghent University (as "an integrated empirical and philosophical study of values, norms and world views")

Other implications

Daleiden provides examples of how science can use empirical evidence to assess the effect that specific behaviours can have on the well-being of individuals and society with regard to various moral issues. He argues that science supports decriminalization and regulation of drugs, euthanasia under some circumstances, and the permission of sexual behaviours that are not tolerated in some cultures (he cites homosexuality as an example). Daleiden further argues that in seeking to reduce human suffering, abortion should not only be permissible, but at times a moral obligation (as in the case of a mother of a potential child who would face the probability of much suffering). Like all moral claims in his book, however, Daleiden is adamant that these decisions remain grounded in, and contingent on empirical evidence.

The ideas of cultural relativity, to Daleiden, do offer some lessons: investigators must be careful not to judge a person's behaviour without understanding the environmental context. An action may be necessary and more moral once we are aware of circumstances. However, Daleiden emphasizes that this does not mean all ethical norms or systems are equally effective at promoting flourishing and he often offers the equal treatment of women as a reliably superior norm, wherever it is practiced.

Criticisms

The idea of a normative science of morality has met with many criticisms from scientists and philosophers. Critics include physicist Sean M. Carroll, who argues that morality cannot be part of science. He and other critics cite the widely held "fact-value distinction", that the scientific method cannot answer "moral" questions, although it can describe the norms of different cultures. In contrast, moral scientists defend the position that such a division between values and scientific facts ("moral relativism") is not only arbitrary and illusory, but impeding progress towards taking action against documented cases of human rights violations in different cultures.

Stephen Jay Gould argued that science and religion occupy "non-overlapping magisteria". To Gould, science is concerned with questions of fact and theory, but not with meaning and morality – the magisteria of religion. In the same vein, Edward Teller proposed that politics decides what is right, whereas science decides what is true.

During a discussion on the role that naturalism might play in professions like nursing, the philosopher Trevor Hussey calls the popular view that science is unconcerned with morality "too simplistic". Although his main focus in the paper is naturalism in nursing, he goes on to explain that science can, at very least, be interested in morality at a descriptive level. He even briefly entertains the idea that morality could itself be a scientific subject, writing that one might argue "... that moral judgements are subject to the same kinds of rational, empirical examination as the rest of the world: they are a subject for science – although a difficult one. If this could be shown to be so, morality would be contained within naturalism. However, I will not assume the truth of moral realism here."

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