Anomalous Resistance Behavior in Bilayer Graphene

Anomalous Resistance Behavior in Bilayer Graphene Observation of Anomalous Resistance Behavior in Bilayer Graphene Yanping Liu 1,2, Wen Siang Lew 2,*and Zongwen Liu 3,* Abstract Our measurement results have shown that bilayer graphene exhibits an unexpected sharp transition of the resistance value in the temperature region 200~250K. We argue that this behavior originates from the interlayer ripple scattering effect between the top and bottom ripple graphene layer. The inter-scattering can mimic the Coulomb scattering, but is strongly dependent on temperature. The observed behavior is consistent with the theoretical prediction that charged impurities are the dominant scatters in bilayer graphene. The resistance increase with increasing perpendicular magnetic field strongly supports the postulate that magnetic field induces an excitonic gap in bilayer graphene. Our results reveal that the relative change of resistance induced by magnetic field in the bilayer graphene shows an anomalous thermally activated property. ______________________________________ Introduction: The electronic properties of monolayer graphene have been extensively studied due to its intriguing energy band structure with linear dispersion around the Dirac point and chirality exhibiting Berry phase of [1]. There is a zero-energy Landau level (LL) with four-fold degeneracy due to interactions between electron spins and valleys in the magnetic field [2-4]. Recently, bilayer graphene became a subject of intense research due to the low energy Hamiltonian of chiral quasiparticles and a Berry phase of [5-8]. It has a double-degeneracy zero-energy Landau level that incorporates two different orbital states with the same energy under an external magnetic field. The bilayer graphene with a Bernal (A-B) configuration loses some features of monolayer graphene and has a unique band structure where the conduction and valence bands are in contact with a nearly quadratic dispersion [5]. In bilayer graphene, a parabolic band structure ( ) with an effective mass m*=0.037, has been calculated by using the interlayer coupling model [9-14]. What makes bilayer graphene an interesting material for study is that the interlayer potential asymmetry can be controlled by an electric field, thus opening an energy gap between the conduction and valence bands [16-18]. Various applications for bilayer graphene are possible due to the fact that its band gap can be modulated by using an external out-of-plane electric field and chemical doping. There is intensive research on bilayer graphene under the application of a perpendicular electric field, however, experimental reports on magnetic transport properties of bilayer graphene are not as well-studied. Recent theoretical work reports on excitonic condensation and quantum Hall ferromagnetism in bilayer graphene [22]. There are interesting features in bilayer graphene due to its extra twofold orbital degeneracy in the LL spectrum, which results in an eightfold -degenerate LL at zero energy. The scattering mechanism of graphene is current ly a subject of intense research and debate. The problem of magneto-transport properties in the presence of Coulomb impurities is still an open research problem. Our understanding of the nature of the disorder and how the mesoscopic ripple effect affects the transport properties still need improvement; hence, a better understanding on the general electric and magnetic transport properties of bilayer graphene is necessary. In this paper, we have systematically investigated the charge transport properties in bilayer graphene as a function of temperature, magnetic field, and electric field. Our measurement results have shown that bilayer graphene exhibits a semi-metallic R-T property and an unexpected sharp transition of the resistance value in the temperature region 200~250K. The longitudinal resistance decreases with increasing temperature and electric field, a behavior that is markedly different from the experimental reports of monolayer graphene. Our results reveal that the energy gap in the bilayer graphene shows an anomalous thermally activated property and increases with. We have shown that this phenomenon originates from a tuneable band structure behavior that can be controlled by a magnetic field, a property that had never previously been observed in bilayer graphene. It has been shown that Raman spectroscopy is a reliable, non-destructive tool for identifying the number of graphene layers and it can be done through the 2D-band deconvolution procedure [23-25]. The Raman spectra of our graphene structure were measured at room temperature using a WITEC CRM200 instrument at 532 nm excitation wavelength in the backscattering configuration [26-28]. Fig.1a shows the characteristic Raman spectrum with a clearly distinguishable G peak and 2D band. The two most intense features are the G peak and the 2D band which is sensitive to the number of layers of graphene. The position of the G peak and the shape of the 2D band confirm the number of layers of graphene. Additionally, the number of layers of graphene can be easily distinguished from the full width half maximum of the 2D band, as its mode changes from a narrow and symmetric feature for monolayer graphene to an asymmetric distribution on the high-energy side for bilayer graphene [27]. The 2D band inset in Fig.1a shows that the Raman spectrum of bilayer graphene is red-shifted and broadened with respect to that of the monolayer graphene. Fig. 1b shows the four terminal resistance as a function of carrier-density n, and the sample shows a pronounced peak at density . Note that the sharp peak in resistance at low n is enhanced by the opening of the small energy gap owing to disorder-induced differences in carrier density between the top and the bottom layers of the flake. We have characterized the current (I)-voltage (V) characteristics of the bilayer graphene via four-terminal measurement, at different temperatures and magnetic fields. Shown in Fig. 2a are the I-V curves for bilayer graphene under the application of various magnetic fields at three different temperatures: 2 K, 200 K and 340 K. The magnetic field is applied in the perpendicular direction to the plane of the graphene. For all the temperatures and magnetic field strengths, the bilayer graphene exhibits a linear I-V curve. This implies that the graphene layer is ohmic in nature. We observed that for a fixed magnetic field, the I-V curve displays a larger gradient at higher temperature than at lower temperature. Interestingly, the gradient of the I-V curve decreases with increasing magnetic field. In our structure, the gradient of the curve corresponds to the conductivity of the graphene layer. Such temperature and magnetic field dependent behaviour of conductivity is characteristic of an intrinsic semiconductor. The decrease in the conductivity of the bilayer graphene with increasing magnetic field is attributed to the excitonic energy gap induced by the magnetic field. This conductivity dependence on the magnetic field suggests that the resistance () of graphene is a qualitative fingerprint of its band gap. In the absence of a magnetic field, the band structure of the bilayer graphene at the Dirac valley has a parabolic dispersion relation. When a magnetic field is present, the band structure is changed to a split Landau level structure [19-21]. Fig. 2(b) is an illustration of the bilayer bandgap and Landau level splitting under the influence of a magnetic field. Inset shows an optical image of the bilayer graphene with the metal contact electrodes. In Fig.2(c) we plot the resistance of the bilayer graphene, as extracted from the I-V curve, as a function of magnetic field for three different temperatures. As the magnetic field was increased in a step of 4T, the resistance increase for each step was different, resulting in a non-linear relationship between the resistance and magnetic field. Interestingly, the observed non-line relationship is markedly different from Zeeman spin-splitting theoretical model with the line relationship, where gap with a free-electron g-factor g=2, where is the Bohr magneton. This potentially indicates sublattice symmetry breaking and gap formation due to many-body correction in this LL [32-34]. This is further confirmation that magnetic field opens an excitonic gap in the bilayer graphene. The temperature dependence of monolayer graphene resistance is mainly attributed to the different scattering mechanisms: Coulomb scattering [35-36], short range scattering [37], and phonon scattering [38-39]. However, the temperature dependence of bilayer graphene resistance has not been established yet. Shown in Fig.3a are the temperature dependence of the resistance of the bilayer graphene under the application of a magnetic field 0T and 12T, respectively. The results show that the resistance of the bilayer graphene drops following non-metallic behaviour as temperature increases from 2K to 340 K. This implies that the bilayer graphene resistors have intrinsic semiconductor properties as mentioned earlier. This can be explained by the decrease in Coulomb scattering with temperature for bilayer graphene due to its parabolic band structure. For B=12T, a similar trend as B=0T is obtained in Fig 3a, where the resistance decreases with increasing temperature. However, the resistance for the entire temperature range is much larger than for B=0T. This indicates that the magnetic field opens an excitonic gap in the bilayer graphene that is thermally activated due to the Coulomb interaction ion-driven electronic instabilities [20, 31]. Ripples are a common feature of cleaved graphene because it is never atomically flat, as it is placed on a substrate such as SiO2 in the term of nanometre-scale deformations or ripples [40-42]. Despite the magnitude of the ripples being quite small, it is still believed to be responsible for the unusual transport behaviour of graphene, also susceptible to adsorbed impurities, defects and the roughness of the underlying substrate [40-43]. On the other hand, it has been shown that suspended graphene films are corrugated on a mesoscopic scale, with out-of-plane deformations up to 1 nm [44-45]. The deformation is a typically smaller than the Fermi wavelengthand these ripples induce predominantly short-range scattering. The observed height variation shows that the surface roughness beyond the atomic-level is intrinsically present in bilayer graphene. Hence, one of the interesting features of corrugation of graphene is that it offers a new experimental opportunity to study how the corrugat ion-induced scattering impacts the transport properties of graphene. It is important to mention that there is a strange sharp threshold like decrease in resistance observed above 200K. The strong temperature dependence is inconsistent with scattering by acoustic phonons. One possible explanation is that the flexural phonons confined within ripples between the top and bottom layer causes the scattering. The presence of the ripple effect exhibits local out-of-plane ripples [44]. Theoretical calculations[41,46] show that the scattering rates for interripple flexural phonons with respect to two-phonon scattering process as, where is the flexural-phonon frequency, the derivative of the nearest-neighbour hopping integral with respect to deformation, a the lattice constant, , and the mass of carbon atom [46]. For low temperatures T () , few flexural modes can be excited inside ripples (). The conductivity of the surface roughness model at the limit at low temperature is[45-46]. As the t emperature increases and typical wavelengths become shorter, short-range scattering excites the flexural phonons. For the high temperature limit, based on the above expression, we can estimate that , which yields ~100 to 1000 at T=300K. The model of quenched-ripple disorder [46] suggested that the electron scattering of the static ripples quenched from the flexural phonon disorder can mimic Coulomb scattering when at room temperature. One should also note that the model predicts stronger temperature dependence (above a certain quenching temperature of about 100K) which is close to our experimental result at about 200K. However, the ripple effect normally leads to a rapid increase in the R-T curve rather than the sudden decrease in R-T as observed for our bilayer graphene. In the absence of a theory to explain the stronger temperature dependence behaviour, we propose that the behaviour is consistent with the ripple effect interlayer scattering instead of interlayer scattering. Fig. 3b shows the schematically illustration of scattering mechanisms in bilayer graphene. For a bilayer graphene, the interlayer scattering between the top and bottom ripple graphene layer is similar to coulomb scattering with stronger dependence on temperature. The rapid decrease in R-T above 200K can be attributed to the transition between the low- and high-T limits in the interlayer ripple effect scattering. On the other hand, it was suggested that the observed strong T dependence could be explained by thermally excited surface polar phonons of the SiO2 substrate [35-38]. The SiO2 optical phonons at the substrate-graphene interface induce an electric field which couples to the carriers in graphene due to it modulating the polarizability [38-39]. However, Coulomb scattering is dominant for bilayer graphene and the substrate surface polar phonon induced field is to some extent screened by the additional graphene layers [39]. Recently it has been shown that the substrate dielectric constant plays an important role in scattering in graphene. Theoretical predictions show that for dielectric constant , Coulomb scattering dominates, while for dielectric constant , short-range scattering dominates, as Coulomb scattering is more strongly screened for materials with a larger dielectric constant. In fact, our observed behaviour is consistent with the theory suggesting that scattering from charged impurities is dominant in graphene. We introduce a relaxation-time approximation and treat the unscreened Coulomb potential as [1,5] where Q is the charge of impurities. Based on the Boltzmann transport theory, we can obtain the bilayer graphene resistivity with massless Dirac-fermions (MDF) at low energies as. For high temperature , , we can obtain the bilayer graphene resistivity as[47], where is the density of impurities per unit volume, is the permittivity of the semiconductor, and is the charge state of the impurity. This shows that the resistance of bilayer graphene limited by Coulomb scattering increases as increases and decreases with increasing temperature. Considering the above analysis, we deduce that the temperature dependence of resistance in bilayer graphene is mainly determined by Coulomb scattering. The short-range scattering is independent of temperature for bilayer graphene, as the density-of-states, the matrix element and the screening function are all energy independent. As a result of the parab olic band structure of bilayer graphene, the energy averaging of the Coulomb scattering time can give rise to the resistivity decreasing proportionality to temperature : . Based on the above discussion, we fit the measured resistance in Fig.3a by using the following model for bilayer graphene:, where and are the resistance due to the Coulomb and short-range scatterings, respectively. Fig.3b shows the relative resistance change under the biased and unbiased magnetic field as a function of temperature, and the dotted line is the fit following the equation , where is the energy gap. The opening of the energy gap due to a potential difference between the two layers and Coulomb interactions could be a cause for this. These considerations explain qualitatively why the resistance of bilayer graphene decreases with increasing temperature. Note that the relative resistance change is a strong function of temperature. At temperatures of 2Kà ¯Ã¢â€š ¬Ã‚ ­180K and 220Kà ¯Ã¢â€š ¬Ã‚ ­250K, the relative resistance strongly increases as temperature increases, indicating that an energy gap forms due to many-body correction in Landau Level. When the temperature incr eases to T >250K, the relative resistance is roughly independent of the increasing temperature; this indicates that the energy gap is mostly stable at high temperatures. On the other hand, with the temperature increase from 180K to 220K, the relative resistance dependence of temperature shows a sharp decrease, which indicates that the energy gap shows an anomalous thermally activated behaviour as a function of temperature. For zero gate voltage (i.e., neutrality point), we measured changes in longitudinal resistance as a function of applied perpendicular field B. Fig. 4a shows the four-terminal longitudinal resistance of bilayer graphene as a function of magnetic field at T= 2K at the charge-neutrality point. We have plotted the resistance per square, because it is independent of a size effect of the sample. As seen from Fig. 4a, the resistance increases nonlinearly with the magnetic field strength followed by a plateau-like phase. One should note that the plateau-like phase in Fig. 4b disappears at higher temperatures. One possible explanation is the augmented sublattice spin-splitting due to the high surface-impurity concentration of the graphene layer [18]. The origin of the nonlinear magnetoresistance increment behaviour is the splitting of Landau level that gives rise to a bandgap opening at the zero energy level [32-34]. In our measurements, we fit our results to an analytical approximation for the non-linear resistance , where is the Boltzmann constant. We found that our results are in good agreement with this equation. These considerations explain qualitatively why the nonlinear resistance increases with the magnetic field. Fig. 5 shows the resistance of bilayer graphene as a function of electric field (E) under different magnetic fields. The dependent characteristics are symmetric due to the chirality of graphene electrons when an applied electric field changes from E to E. The normalized resistance curve describes the response under the applied magnetic field in the range of B=0T to B=12T and the temperatures of 2-340K. The results demonstrate that when the magnetic field increases from 0T to 12T at low temperatures (2à ¯Ã¢â€š ¬Ã‚ ­200K) and low electric field (E), the resistance of bilayer graphene drops significantly. The larger slump in the resistance at lower temperature T=2K and low electric field as the increasing of electric field are due to Coulomb scattering by impurities, which is a strong function of temperature. On the other hand, at high temperatures (T >200K) and electric fields (E>0.01 ), the resistance of bilayer graphene show a linear decrease. This can be explained by the scatteri ng from thermally excited surface polar phonons of the substrate being screened by the additional top graphene layers [39]. This further confirms that at high temperatures, the scattering induced by the electric field on the substrate surface polar phonons is significantly screened between top and bottom layers in bilayer graphene. In our experiment, temperature and magnetic field dependence of resistance of bilayer graphene was investigated. Intrinsic semiconductor behaviour at the range of temperature is 2K-340K was observed. The strange sharp threshold-like decrease in resistance around 200K is unexpected, and we attribute it to the presence of mesoscopic ripples between the top and bottom layer. Our results reveal that the energy gap in the bilayer graphene is thermally dependent. This potentially indicates the sublattice symmetry breaking and an energy gap formation due to Landau Level splits. The obtained results are important for the better understanding of magnetic field induced high resistance and provide indications of a theoretically predicted magnetic field induced excitonic gap. Acknowledgements Y. L would like to thank Prof. Wang and Prof. Yao for his useful discussions. This work was supported in part by the NRF-CRP program (Multifunctional Spintronic Materials and Devices) and the Agency for Science, Technology and Research (A*STAR) SERC grant (082 101 0015). The authors thank Sun Li and Li Yuanqing for their assistance in experimental measurements. Experimental section The bilayer graphene samples for this study were prepared using mechanical exfoliation techniques [2] from the bulk highly oriented pyrolitic graphite (grade ZYA, SPI Supplies) and transferred onto the surface of a lightly doped silicon substrate covered with a 300-nm thick layer of thermally grown , The doped silicon substrate and were used as back-gate and gate dielectric, respectively. Graphene electrical electrodes were patterned using photolithography techniques. A pair of ohmic Cr/Au (5nm/100nm) contacts were deposited via thermal evaporation at a background pressure of 10à ¯Ã¢â€š ¬Ã‚ ­7 mbar and subsequently lifted off in warm acetone. Electronic transport measurements have been carried out on multiple samples, using PPMS (Quantum Design) with a fixed excitation current of 10 . Electrical measurements were performed in the temperature range 2K ~340K and a magnetic field up to 12T was applied. 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Criminal Justice and Technology

Computer and telecommunications technologies in criminal justice system have developed at an extraordinary rate. Increased computing power, advances in data transmission and attractive and user-friendly graphic interfaces present law enforcement agencies with unprecedented capacity to collect, store, analyze and share data with stakeholders inside and outside of government. Technology in criminal justice field represents a tool to help local law enforcement achieve its broadened and increasingly complex mission. But whether this capability is fully realized, and at what pace, is not a foregone conclusion. Preliminary studies suggest that if its integration is not well managed, some aspects of technology may meet with resistance among officers and other staff, particularly when such technology is perceived as unfairly intrusive or technically cumbersome. Historically, technological innovation has served as the catalyst for dramatic changes in the organization of police work and has presented both opportunities and challenges to police and other criminal justice practitioners, according to Janet Chan, a social scientist who has studied how technology affects the way police do their jobs. Noting that information is the stocking- trade of policing, Chan has identified three general imperatives driving law enforcement’s investment in information technology: 1. A Technology-driven imperative to improve effectiveness and efficiency by increasing the capacity to store and process large volumes of data; Improving intelligence and investigative capabilities; and providing ready access to criminal records and other kinds of relevant data. 2. An Information-driven imperative to satisfy increasing demands to share data with external entities, including other government agencies, the public and other outside entities such as insurance companies and other businesses; and 3. A Policy-driven imperative to meet the requirements of new forms of police management and accountability, in terms of probity, cost effectiveness, and procedural regularity, including systems designed to provide early warning for police use of force complaints. Under this new order, police are being scrutinized internally by management systems, surveillance technologies, internal audits and investigations and externally by watchdog agencies, public complaint systems and central auditors. As Chan notes, information technology provides a tool not only for policing citizens, but also for policing the police. Important technologies in the Criminal Justice System DNA- The past decade has seen great advances in a powerful criminal justice tool: deoxyribonucleic acid, or DNA. This one can be used to identify criminals with incredible accuracy when biological evidence exists. By the same token, DNA can be used to clear suspects and exonerate persons mistakenly accused or convicted of crimes. In all, DNA technology is increasingly vital to ensuring accuracy and fairness in the criminal justice system. DNA is generally used to solve crimes in one of two ways. In cases where a suspect is identified, a sample of that person’s DNA can be compared to evidence from the crime scene. The results of this comparison may help establish whether the suspect committed the crime. In cases where a suspect has not yet been identified, biological evidence from the crime scene can be analyzed and compared to offender profiles in DNA databases to help identify the perpetrator. Crime scene evidence can also be linked to other crime scenes through the use of DNA databases. DNA evidence is generally linked to DNA offender profiles through DNA databases. In the late 1980s, the federal government laid the groundwork for a system of national, state, and local DNA databases for the storage and exchange of DNA profiles. This system, called the Combined DNA Index System (CODIS), maintains DNA profiles obtained under the federal, state, and local systems in a set of databases that are available to law enforcement agencies across the country for law enforcement purposes. CODIS can compare crime scene evidence to a database of DNA profiles obtained from convicted offenders. CODIS can also link DNA evidence obtained from different crime scenes, thereby identifying serial criminals. In order to take advantage of the investigative potential of CODIS, in the late 1980s and early 1990s, states began passing laws requiring offenders convicted of certain offenses to provide DNA samples. Currently all 50 states and the federal government have laws requiring that DNA samples be collected from some categories of offenders. Fingerprints- offer an infallible means of personal identification. That is the essential explanation for their having supplanted other methods of establishing the identities of criminals reluctant to admit previous arrests. The science of fingerprint Identification stands out among all other forensic sciences for many reasons, including the following: * Has served all governments worldwide during the past 100 years to provide accurate identification of criminals. No two fingerprints have ever been found alike in many billions of human and automated computer comparisons. Fingerprints are the very basis for criminal history foundation at every police agency on earth. * Established the first forensic professional organization, the International Association for Identification (IAI), in 1915. * Established the first professional certification program for forensic scientists, the IAI's Certified Latent Print Examiner program (in 1977), issuing certification to those meeting stringent criteria and revoking certification for serious errors such as erroneous identifications. * Remains the most commonly used forensic evidence worldwide – in most jurisdictions fingerprint examination cases match or outnumber all other forensic examination casework combined. * Continues to expand as the premier method for identifying persons, with tens of thousands of persons added to fingerprint repositories daily in America alone – far outdistancing similar databases in growth. * Worldwide, fingerprints harvested from crime â€Å"scenes lead to more suspects and generate more evidence in court than all other forensic techniques combined†. Other visible human characteristics change – fingerprints do not.

Obstacle Essay Topics Fundamentals Explained

Obstacle Essay Topics Fundamentals Explained Obstacle Essay Topics for Dummies You shouldn't be abashed by your failures and search for essay examples or persuasive essay prompts which may aid you with certain troubles and questions. It is dependent upon the circumstance and which essay topic you select. Lastly, review your essay many times. Don't allow the urge to set yourself apart block you from picking a frequent essay topic. You'll observe a similar structure in a lot of the essays. To compose a persuasive essay first you have to know the definition of persuasive. Your essays ought to be unique. These seven sample essays respond to a wide range of thought-provoking questions. Throughout one's life obstacles have a tendency to become in the manner in the shape of disguises that aren't always pretty. Not everything includes ease, and that is the reason why we have to learn how to overcome the typical obstacles in life. From time to time, life obstacles can't be the key of our happiness. Be cautious to prevent online social distractions also. Fast food nation essay sample the american fast food sector is the greatest cheapness, and wide access to fast food can bring about general wellbeing. Its a reality check to observe which you aren't perfect. Many students used to fall in the trap of writing about the very same banal, limited, and classic scope of failures. Life, Death and Obstacle Essay Topics To begin with, you must tie it to the preceding paragraph by utilizing a transition sentence. Application essays about challenges reveal how you respond to difficulty to folks who are quite interested in how you'll deal with the subsequent four years by yourself. It's very valuable to take writing apart as a way to see just the way that it accomplishes its objectives. The application was, occasionally, arduous and difficult to complete. There isn't a prompt to direct you, which means you must ask yourself the questions that will get at the center of the story you would like to tell. When facing a challenge, it's simple to stop. Various things to various men and women, since the situation demanded. Suddenly, you're in a totally new situation, and will need to do something, but you need zero idea what. If you decide to try it, always earn a connection back to the scholarship. Explain your commitments, and you'll be the sort of student colleges find immensely attractive. The Common App essay is just one of the biggest elements of the college application and students frequently don't know the best places to get started. Let's start with the most elementary point to know more about the scholarship application essay. Graduating high school and going to college has ever been an extremely important goal I have always wished to reach. You may not understand what you would like to do with your career. In most instances the way to do this is for students to further their education beyond merely a high school diploma. Describe an on-line marketplace for unique heights of fame football coach of different essays. The Number One Question You Must Ask for Obstacle Essay Topics Your stories aren't debatable. Days which would never appear to end. Allow it to sit for a couple days untouched. There is going to be struggle, there'll be bad days. What You Should Do to Find Out About Obstacle Essay Topics Before You're Left Behind Now our goals are reached, we can let out a sigh of relief and say our lives are a great deal better. In addition, there are immigrant families that had a tough transition. You're attempting to show colleges your very best self, therefore it might appear counterintuitive to willingly acknowledge a time you struggled. Whether it's a main school student struggling to complete his homework or a friend grieving over a lost loved one, I understand that I'm responsible not only for my own self but also for the folks around me. Obstacle Essay Topics: the Ultimate Convenience! It's All About Introductions The very first thing which you have to do when you wish to compose an extremely impressive essay is to develop a really good introduction. Having grammar mistakes can destroy your odds of winning the scholarship. I love the direction you have organized and presented the translation. In Paragraph 5, you use the word you (But if you would like to attain something) when you're attempting to make an overall statement and aren't actually attempting to tell the reader what things to do.

The Theory Of Human Matter - 1179 Words

Humans, being made of flesh, bone, and sinew, as a whole are consider material objects. This is concept of human matter is normally referred to as the body. However, unlike other nonconscious objects made of matter, humans have a somewhat unique ability to create abstract opinions and thoughts. At this time we are the only species to have the ability formulate explanations for our own existence. Essentially stating that, we humans have minds . The two general aspects that make up the thing we call human are thought to be a mind and body. The brain and the mind are often mistakenly identified as one in the same. When we talk about the mind in a philosophical sense we are referring to the mental processes that make up you: your thoughts, beliefs and consciousness; the body, however, is the physical aspect of thought. It is the brain, the firing of neurons, and how the brain is organized. This is idea of a separation of mind and body is known as dualism. It’s opposing belief, m onism, is a more scientific view of the mind body problem in that they rely commonly on only what they can observe in the body being that they believe that the body and mind are one. I don’t discredit the work and possibility of the existence of the monist view, I simply am an optimistic and found the dualist approach more appealing in approaching the mind body problem. The theory of mind-body dualism created by Rene Descartes, a famous philosopher and mathematician, stated that both mind and body areShow MoreRelatedThe Theories Of Human Development774 Words   |  4 PagesTheories of Human development are relevant and matter in the â€Å"real world†. In my clinical practice as a psychologist-in-training, I have found human development theories to be very useful in conceptualizing and understanding my client’s distress. I used theoretical frameworks that are based on theories of human development to guide my interventions in therapy. For example, as a brief psychodynamic clinician, I look to Freud’s theory of anxiety to understand how distress was developed for my clientsRead MoreThe Book Brave New World 1481 Words   |  6 PagesAldous Leonard Huxley, there are many topics covered about the world, freedom, and men. One of the topics discussed is the theory of evolution. There are many arguments presented about how the world and people evolved. There are different arguments created by creationists and evolutionists. For the creationists, everything is created by a creator such as God and that matter was formed by him to create the earth and even people on earth as well as other creatures in the universe. On the other handRead MoreMargaret Cavendish And The Scientific Revolution1115 Words   |  5 Pagesher own theory on atoms. Though her atomic theory contains many scientific Renaissance ideals, it is still seen as a major contribution of thought during the Scientific Revolution. To begin with, in order to understand the philosophies of Margaret Cavendish one must also understand the Scientific Revolution. The Scientific Revolution was a revolution in both thought and methodology. During the Renaissance science comprised of the organic theories of the magicians and vitalistic theories createdRead MoreEthics1435 Words   |  6 Pagesvalue in matters of human conduct.While virtually all people are concerned with making ethical judgments and decisions, philosophers in particular are concerned to  Ã‚  Ã‚  Ã‚  Ã‚  Ã‚  Ã‚  Ã‚  Ã‚  Ã‚  Ã‚  Ã‚   a) explicate the nature of such judgments in general  and  Ã‚  Ã‚  Ã‚  Ã‚  Ã‚  Ã‚  Ã‚  Ã‚  Ã‚  Ã‚  Ã‚   b) provide criteria for determining what is ethically right or wrong, and  Ã‚  Ã‚  Ã‚  Ã‚  Ã‚  Ã‚  Ã‚  Ã‚  Ã‚  Ã‚  Ã‚   c) analyze the grounds or reasons we have for holding them to be correct.Those concerned exclusively with telling us what is right or wrong, good or bad, in matters of humanRead MoreShould Psychol ogy Be Considered As A Science?1353 Words   |  6 Pages‘scientific study of human behaviour and cognitive processes.’ Science is generally defined as the ‘systematic way or method of obtaining knowledge’ (Merriam-Webster, 2008). When we think of science, we think of Biology, Chemistry and Physics. Psychology is often thought of as just ‘common sense’, however many of the perspectives in Psychology such as Biological, Behaviourist and Cognitive assert that they are scientific. There are other perspectives in Psychology such as Psychodynamic theory and HumanistRead MoreDiscuss the advantages and disadvantages of a scientific approach to the study of society.1607 Words   |  7 PagesScientific approaches to understanding the world can be distinguished from other approaches in two fundamental and irrelevant ways, firstly, an approach that claim to be scientific irrespective of whether or not it originates in the field of natural or human scien ce must demonstrably have empirical relevance to the world. Empirical relevance involves showing that any statements, descriptions and explanations used or derived from this approach can be verified or checked out in the world and secondly, anRead MoreEssay on The Identity Theory529 Words   |  3 PagesThe Identity Theory #65279; Mental processes are physical is equivalent to what is coined The Identity Theory. Smarts theses is that mental events are identical to brain processes. The definition of neurophysiological is to say the science of neurons dealing with living matter such as the brain. Smart discounts Cartesian Dualism that depicts the mind as a separate entity than the physical body. In addition, Smarts theory is a posteriori claim, which is to say that through an observationRead MoreAbsolute Realism Vs. Hylemorphism1309 Words   |  6 Pagescompared to Plato as an â€Å"absolute realist.† Generally speaking, Plato’s interpretation of â€Å"what is real,† reflected in his absolute realism, differs from that of Aristotle’s, reflected in his hylemorphism, to a large extent; besides, Aristotle’s theory of matter and form, is the more convincing one because of the soundness of his arguments and in-depth analysis of the nature of being. Given that Plato and Aristotle are both realists, they are explicitly distinguished from the nominalists or the conceptualistsRead More A Philosophical Criticism of Augustine and Aquinas Essay1548 Words   |  7 PagesA Philosophical Criticism of Augustine and Aquinas: The Relationship of Soul and Body       The relationship of the human soul and physical body is a topic that has mystified philosophers, scholars, scientists, and mankind as a whole for centuries. 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