As in the case for total energy, though, the total entropy in the climate system is relatively steady. Entropy Definition. The following table shows how this concept applies to a number of common processes. Create a submicroscopic sketch of the system, record data from the monitors, and write down your submicroscopic observations. entropy is a fundamental function of a state. A very disordered system (a mixture of gases at a high temperature, for example) will have a high entropy.

The entropy of a system at absolute zero is typically zero, and in all cases is determined only by the number of different ground states it has. The third law of thermodynamics establishes the zero for entropy as that of a perfect, pure crystalline solid at 0 K. Entropy. We also have . wrev = PV, we can express Equation 13.4.3 as follows: U = qrev + wrev = TS PV. Entropy Equation. where p x is the probability density function (PDF) of signal x (n). Our payment system is built using Stripe which allows you to purchase with a credit or debit card. . More discouraging yet, the entropy in my office is increasing. One can also solve this problem via the microcanonical ensemble, similar to problem 1. 5 D.I.Y. There is a system with four energy levels . .

2Freeexpansion Anexamplethathelpselucidatethedi erentde nitionsofentropyisthefreeexpansionofagas fromavolumeV 1toavolumeV 2. Consider a particle is confined in a three-level system. P138.7 Derive an expression for the molar entropy of an equally spaced three- level system; taking the spacing as a ; Question: P138.7 Derive an expression for the molar entropy of an equally spaced three- level system; taking the spacing as a As we have seen this is required unless the entropy becomes singular (infinite). There is yet another way of expressing the second law of thermodynamics. 4.1.

This problem is typically solved by using the so-called LaGrange Method of Undetermined Multipliers. Entropy Entropy (S) is a thermodynamic state function which can be described qualitatively as a measure of the amount of disorder present in a system. Initially the two systems have the same temperature and volume and are made up of di erent species, but the same number of particles. Entropy is the measure of the disorder of a system.

The second law of thermodynamics states that a spontaneous process increases the entropy of the universe, Suniv > 0. That's because the climate is an open system that receives much less entropy from the Sun . First,considertheBoltzmannentropy,de . The entropy change of a system can be negative during a process (Fig. Now we have set up the system, let's explain what we mean by a microstate and enumerate them. For liquid state, still the particles are moving but less freely than the gas particles and more than . Past this level, the synergy began to decrease .

In this chapter we present a statistical interpretation of both temperature and entropy. Qualitative Predictions about Entropy Entropy is the randomness of a system. October 14, 2019 October 14, 2019. . Among them, P i is the normalized value of the original data, X i is the original data value, e i is the entropy value of the index, W i is the weight value of each index, S i is the comprehensive development level score of each city, k=ln(n) > 0, satisfies e i 0. Entropy (i.e. The time evolution of the system, in atomic ladder and configurations, is solved exactly assuming a coherent-state as the initial atomic state. Entropy and Probability (A statistical view) Entropy ~ a measure of the disorder of a system.

To make the mathematics simple we use a system with discrete, equally-spaced energy levels, E n= n., where n = 1,2,3 G(quantum #) These are the energy levels for a mass on a spring: This system was studied in P214. One can show that the Helmholtz free energy decreases in electron in a double quantum dot Tunneling couples the lowest level on the . The idea of software entropy, first coined by the book Object-Oriented Software Engineering, was influenced by the scientific definition . This is a function of the . This research analyzes the basis for the . In equations, entropy is usually denoted by the letter S and has units of joules per kelvin (JK 1) or kgm 2 s 2 K 1. Here are the various causes of the increase in entropy of the closed system are: Due to external interaction: In closed system the mass of the system remains constant but it can exchange the heat with surroundings. Entropy is a measure of the degree of spreading and sharing of thermal energy within a system. 3), but entropy generation cannot. Results: All the entropy and MDFA indices could track the changes in EEG pattern during different anesthesia states. The same denition (entropy as a logarithm of the number of states) is true for any system with a discrete set of states. Entropy is a degree of uncertainty. For example, suppose the system can only exist in three states (1, 2 and 3). This is why low quality heat cannot be transferred completely into useful work. First,considertheBoltzmannentropy,de . Conversely, processes that reduce the number of microstates, W f W i, yield a decrease in system entropy, S 0. Abstract Based on the micro-canonical ensemble (MCE) theory and the method of steepest descend, we rederive a formula for the entropy and the temperature in the general three-level system. For example, con-sider the set of N two-level systems with levels 0 and .

Notice that it is a negative value. The knee and ankle joint produced the lowest levels of variability across the three orthogonal joint motions . Assume independent and distinguishable molecules. (a) 6.5x104 J/K (b) 4.7x1024 m kg-s.K (c) 1.5x1023 m kg -s.K -24 (d) -1.5x10 J/K Three-Level Indicators. randomness) of the system decreases because the crystalline structure of NaCl(s) formed is highly ordered and very regular i.e. If the distribution probability is the system is in quantum state 1 and there is no randomness. This is a highly organised and ordered system. A useful analogy is to think about the number of ways . a) this cannot be possible. A very regular, highly ordered system (diamond, for example) will have a very low entropy. Therefore, the system entropy will increase when the amount of motion within the system increases. more disorder greater entropy Entropy of a substance depends on d) none of the mentioned. 2.3 Entropy and the second law of thermodynamics 2.3.1 Order and entropy Suppose now that somehow or other we could set up the spins, in zero magnetic field, such that they What is the entropy of the system. Figure 1: With entropy of a closed system naturally increasing, this means that the energy quality will decrease. Entropy measures the amount of decay or disorganization in a system as the system moves continually from order to chaos. Higher entropy indicates higher uncertainty and a more chaotic system. Owing to the wider spacing of the quantum levels in system , fewer quantum levels are accessible, yielding only two possible microstates. Three PE measures outperformed the other entropy indices, with less baseline variability, higher coefficient of determination (R (2)) and prediction probability, and RPE performed best; ApEn and SampEn discriminated BSP best.

View Answer. Derive an expression for the molar entropy of an equally spaced three-level system. Disorder can be of 3 types- Positional, Vibrational and Configurational Thermobarometric models is an excellent case . Recognizing that the work done in a reversible process at constant pressure is. The node is the purest if it has the instances of only one class. We solve the Nakajima-Zwanzig (NZ) non-Markovian master equation to study the dynamics of different types of three-level atomic systems interacting with bosonic Lorentzian reservoirs at zero temperature. Any change in the heat content of the system leads to disturbance in the system, which tends to increase the entropy of the system. For an ideal gas it . This "spreading and sharing" can be spreading of the thermal energy into a larger volume of space or its sharing amongst previously inaccessible microstates of the system. Conduct two more trials with the heat dial set to levels 2 and 3. We discuss the appearance of atomic squeezing and calculate the atomic spin squeezing and the atomic entropy squeezing. You ended up with 1 mole of carbon dioxide and two moles of liquid water. .

If we look at the three states of matter: Solid, Liquid and Gas, we can see that the gas particles move freely and therefore, the degree of randomness is the highest. revealed several task-driven and general patterns of postural variability that are relevant to understanding the entropy of the postural system. We investigate the dynamical behavior of the atom-photon entanglement in a V-type three-level quantum system using the atomic reduced entropy. Entropy is a measure of the disorder of a system. Total entropy at the end = 214 + 2 (69.9) = 353.8 J K -1 mol -1. Entropy change = 353.8 - 596 = -242.2 J K -1 mol -1. Entropy is an advanced Minecraft ghost client developed with quality in mind. Entropy exists in all systems, nonliving and living, that possess free energy for doing work. 13. Microstates depend on molecular motion. Consider a system in two different conditions, for example 1kg of ice at 0 o C, which melts and turns into 1 kg of water at 0 o C. We associate with each condition a quantity called the entropy. Abstract In this paper, we use the quantum field entropy to measure the degree of entanglement in the time development of a three-level atom interacting with two-mode fields including all acceptable kinds of nonlinearities of the two-mode fields. Entropy is a scientific concept as well as a measurable physical property that is most commonly associated with a state of disorder, randomness, or uncertainty. Entropy is a concept that was derived in the nineteenth century during the study of thermodynamic systems. However, the energy conservation law (the first law of . Qualitatively, entropy is simply a measure how much the energy of atoms and molecules become more spread out in a process and can be defined in terms of statistical probabilities of a system or in terms of the other thermodynamic quantities . Entropy also describes how much energy is not available to do work. Entropy. In accordance with the second law of thermodynamics, irreversibility in the climate system permanently increases the total entropy of the universe. Entropy is calculated for every feature, and the one yielding the minimum value is selected for the split. All of our modules are carefully developed allowing for a balanced level of customizability and ease of use. We consider the problem of an atomic three-level system in interaction with a radiation field. For example, the entropy increases when ice (solid) melts to give water (liquid). Assume independent and distinguishable molecules. Answer: c If energy of the set is E then there are L = E= upper levels occupied. 2 Entropy and irreversibility 3 3 Boltzmann's entropy expression 6 4 Shannon's entropy and information theory 6 5 Entropy of ideal gas 10 .

How can this statement be justified? Entropy and Disorder Entropy is a measure of disorder. Ways to Lower Entropy For best results, consistent practice is necessary. level systems Examples of two level systems: -A Spin 1/2 particle -A 'two-level atom' An atom driven with an oscillating E-field whose frequency closely matches one of the atomic transition frequencies -Particle in a double-well potential E.g. This path will bring us to the concept of entropy and the second law of thermodynamics. 4.2.2. Thus the change in the internal energy of the system is related to the change in entropy, the absolute temperature, and the PV work done. This molecular-scale interpretation of entropy provides a link to the probability that a process will occur as illustrated in the next paragraphs. It is the measure of impurity in a bunch of examples. From a chemical perspective, we usually mean molecular disorder. Entropy (i.e. We investigate the dynamical behavior of the atom-photon entanglement in a V-type three-level quantum system using the atomic reduced entropy. The increase of entropy principle can be summarized as follows: Sgen > 0 Irreversible process Sgen = 0 Reversible process Sgen < 0 Impossible process Fig. The term and the concept are used in diverse fields, from classical thermodynamics, where it was first recognized, to the microscopic description of nature in statistical physics, and to the principles of information theory. The amount of entropy depends on the number of possible energy levels that the individual particles can have. Question 9) K+K Chapter 6, Problem 6 Entropy of Mixing. It can be seen from Figure 7 that the weight of each indicator is different, indicating that the importance of each indicator is different, and the focus of government management is also different. It is shown that an atom and photons are entangled at the steady-state; however disentanglement can also be achieved in an special condition. Entropy is given as. It's based on the Second Law of Thermodynamics, which states that the total entropy of an isolated system cannot decrease with time. On a cold winter day, Pelle spills out 1.0 dl of water with a temperature of 20 C. . The entropy of any substance is a function of the condition of the substance. Also, scientists have concluded that in a spontaneous process the entropy of process must increase. The result is an underdetermined system of linear equations, with three known values (the mutual information terms) and four unknown values (the partial information terms). Entropy. To address the description of entropy on a microscopic level, we need to state some results concerning microscopic systems. Entropy is mainly associated with heat and temperature. Our motivation is to discuss the entropy squeezing from another point of view by considering the entropy squeezing for the field instead of the atom. b) this is possible because the entropy of an isolated system can decrease. All you need to know is the energy level formula (E n= n ). The probability of finding the particle in first level is 0.38, for second level 0.36, and for third level it is 0.26. Entropy is the tendency of complex systems, to progressively move towards chaos, disorder, death, and deterioration. Thus, measuring the entropy level of the universe sheds light on both the . It can be expresses by 'S'=q/t The term is coined by Rudolf Clausius. However, in a gas the particles are free to move randomly and with a range of speeds.

randomness) of the system increases when the pressure decreases from 3 atm to 1 atm. We will illustrate the concepts by minima) of a function, e.g. The past three lectures: we have learned about thermal energy, how it is stored at the microscopic level, and how it can be transferred from one system to another. It will even increase more when water is evaporated to steam (gas). 4: The entropy of a substance increases ( S > 0) as it transforms from a relatively ordered solid, to a less-ordered liquid, and then to a still less-ordered gas. The level of chaos in the data can be calculated using entropy of the system. 3. We calculate the atomic spin-squeezing, the atomic entropy-squeezing, and their variances. Example: N = 20,000; E = 10,000; three energy levels 1=0, 2=1, 3=2. We study the dynamics of global quantum discord and von Neumann entropy for systems composed of two, three, and four two-level atoms interacting with the single-mode coherent field under the influence of a nonlinear Kerr medium. Higher entropy indicates higher uncertainty and a more chaotic system. For processes involving an increase in the number of microstates, W f > W i, the entropy of the system increases, S > 0. Because work is obtained from ordered molecular motion, the amount of entropy is also a measure of the molecular disorder, or randomness, of a system.

The entropy of a system at absolute zero is typically zero, and in all cases is determined only by the number of different ground states it has. The third law of thermodynamics establishes the zero for entropy as that of a perfect, pure crystalline solid at 0 K. Entropy. We also have . wrev = PV, we can express Equation 13.4.3 as follows: U = qrev + wrev = TS PV. Entropy Equation. where p x is the probability density function (PDF) of signal x (n). Our payment system is built using Stripe which allows you to purchase with a credit or debit card. . More discouraging yet, the entropy in my office is increasing. One can also solve this problem via the microcanonical ensemble, similar to problem 1. 5 D.I.Y. There is a system with four energy levels . .

2Freeexpansion Anexamplethathelpselucidatethedi erentde nitionsofentropyisthefreeexpansionofagas fromavolumeV 1toavolumeV 2. Consider a particle is confined in a three-level system. P138.7 Derive an expression for the molar entropy of an equally spaced three- level system; taking the spacing as a ; Question: P138.7 Derive an expression for the molar entropy of an equally spaced three- level system; taking the spacing as a As we have seen this is required unless the entropy becomes singular (infinite). There is yet another way of expressing the second law of thermodynamics. 4.1.

This problem is typically solved by using the so-called LaGrange Method of Undetermined Multipliers. Entropy Entropy (S) is a thermodynamic state function which can be described qualitatively as a measure of the amount of disorder present in a system. Initially the two systems have the same temperature and volume and are made up of di erent species, but the same number of particles. Entropy is the measure of the disorder of a system.

The second law of thermodynamics states that a spontaneous process increases the entropy of the universe, Suniv > 0. That's because the climate is an open system that receives much less entropy from the Sun . First,considertheBoltzmannentropy,de . The entropy change of a system can be negative during a process (Fig. Now we have set up the system, let's explain what we mean by a microstate and enumerate them. For liquid state, still the particles are moving but less freely than the gas particles and more than . Past this level, the synergy began to decrease .

In this chapter we present a statistical interpretation of both temperature and entropy. Qualitative Predictions about Entropy Entropy is the randomness of a system. October 14, 2019 October 14, 2019. . Among them, P i is the normalized value of the original data, X i is the original data value, e i is the entropy value of the index, W i is the weight value of each index, S i is the comprehensive development level score of each city, k=ln(n) > 0, satisfies e i 0. Entropy (i.e. The time evolution of the system, in atomic ladder and configurations, is solved exactly assuming a coherent-state as the initial atomic state. Entropy and Probability (A statistical view) Entropy ~ a measure of the disorder of a system.

To make the mathematics simple we use a system with discrete, equally-spaced energy levels, E n= n., where n = 1,2,3 G(quantum #) These are the energy levels for a mass on a spring: This system was studied in P214. One can show that the Helmholtz free energy decreases in electron in a double quantum dot Tunneling couples the lowest level on the . The idea of software entropy, first coined by the book Object-Oriented Software Engineering, was influenced by the scientific definition . This is a function of the . This research analyzes the basis for the . In equations, entropy is usually denoted by the letter S and has units of joules per kelvin (JK 1) or kgm 2 s 2 K 1. Here are the various causes of the increase in entropy of the closed system are: Due to external interaction: In closed system the mass of the system remains constant but it can exchange the heat with surroundings. Entropy is a measure of the degree of spreading and sharing of thermal energy within a system. 3), but entropy generation cannot. Results: All the entropy and MDFA indices could track the changes in EEG pattern during different anesthesia states. The same denition (entropy as a logarithm of the number of states) is true for any system with a discrete set of states. Entropy is a degree of uncertainty. For example, suppose the system can only exist in three states (1, 2 and 3). This is why low quality heat cannot be transferred completely into useful work. First,considertheBoltzmannentropy,de . Conversely, processes that reduce the number of microstates, W f W i, yield a decrease in system entropy, S 0. Abstract Based on the micro-canonical ensemble (MCE) theory and the method of steepest descend, we rederive a formula for the entropy and the temperature in the general three-level system. For example, con-sider the set of N two-level systems with levels 0 and .

Notice that it is a negative value. The knee and ankle joint produced the lowest levels of variability across the three orthogonal joint motions . Assume independent and distinguishable molecules. (a) 6.5x104 J/K (b) 4.7x1024 m kg-s.K (c) 1.5x1023 m kg -s.K -24 (d) -1.5x10 J/K Three-Level Indicators. randomness) of the system decreases because the crystalline structure of NaCl(s) formed is highly ordered and very regular i.e. If the distribution probability is the system is in quantum state 1 and there is no randomness. This is a highly organised and ordered system. A useful analogy is to think about the number of ways . a) this cannot be possible. A very regular, highly ordered system (diamond, for example) will have a very low entropy. Therefore, the system entropy will increase when the amount of motion within the system increases. more disorder greater entropy Entropy of a substance depends on d) none of the mentioned. 2.3 Entropy and the second law of thermodynamics 2.3.1 Order and entropy Suppose now that somehow or other we could set up the spins, in zero magnetic field, such that they What is the entropy of the system. Figure 1: With entropy of a closed system naturally increasing, this means that the energy quality will decrease. Entropy measures the amount of decay or disorganization in a system as the system moves continually from order to chaos. Higher entropy indicates higher uncertainty and a more chaotic system. Owing to the wider spacing of the quantum levels in system , fewer quantum levels are accessible, yielding only two possible microstates. Three PE measures outperformed the other entropy indices, with less baseline variability, higher coefficient of determination (R (2)) and prediction probability, and RPE performed best; ApEn and SampEn discriminated BSP best.

View Answer. Derive an expression for the molar entropy of an equally spaced three-level system. Disorder can be of 3 types- Positional, Vibrational and Configurational Thermobarometric models is an excellent case . Recognizing that the work done in a reversible process at constant pressure is. The node is the purest if it has the instances of only one class. We solve the Nakajima-Zwanzig (NZ) non-Markovian master equation to study the dynamics of different types of three-level atomic systems interacting with bosonic Lorentzian reservoirs at zero temperature. Any change in the heat content of the system leads to disturbance in the system, which tends to increase the entropy of the system. For an ideal gas it . This "spreading and sharing" can be spreading of the thermal energy into a larger volume of space or its sharing amongst previously inaccessible microstates of the system. Conduct two more trials with the heat dial set to levels 2 and 3. We discuss the appearance of atomic squeezing and calculate the atomic spin squeezing and the atomic entropy squeezing. You ended up with 1 mole of carbon dioxide and two moles of liquid water. .

If we look at the three states of matter: Solid, Liquid and Gas, we can see that the gas particles move freely and therefore, the degree of randomness is the highest. revealed several task-driven and general patterns of postural variability that are relevant to understanding the entropy of the postural system. We investigate the dynamical behavior of the atom-photon entanglement in a V-type three-level quantum system using the atomic reduced entropy. Entropy is a measure of the disorder of a system. Total entropy at the end = 214 + 2 (69.9) = 353.8 J K -1 mol -1. Entropy change = 353.8 - 596 = -242.2 J K -1 mol -1. Entropy is an advanced Minecraft ghost client developed with quality in mind. Entropy exists in all systems, nonliving and living, that possess free energy for doing work. 13. Microstates depend on molecular motion. Consider a system in two different conditions, for example 1kg of ice at 0 o C, which melts and turns into 1 kg of water at 0 o C. We associate with each condition a quantity called the entropy. Abstract In this paper, we use the quantum field entropy to measure the degree of entanglement in the time development of a three-level atom interacting with two-mode fields including all acceptable kinds of nonlinearities of the two-mode fields. Entropy is a scientific concept as well as a measurable physical property that is most commonly associated with a state of disorder, randomness, or uncertainty. Entropy is a concept that was derived in the nineteenth century during the study of thermodynamic systems. However, the energy conservation law (the first law of . Qualitatively, entropy is simply a measure how much the energy of atoms and molecules become more spread out in a process and can be defined in terms of statistical probabilities of a system or in terms of the other thermodynamic quantities . Entropy also describes how much energy is not available to do work. Entropy. In accordance with the second law of thermodynamics, irreversibility in the climate system permanently increases the total entropy of the universe. Entropy is calculated for every feature, and the one yielding the minimum value is selected for the split. All of our modules are carefully developed allowing for a balanced level of customizability and ease of use. We consider the problem of an atomic three-level system in interaction with a radiation field. For example, the entropy increases when ice (solid) melts to give water (liquid). Assume independent and distinguishable molecules. Answer: c If energy of the set is E then there are L = E= upper levels occupied. 2 Entropy and irreversibility 3 3 Boltzmann's entropy expression 6 4 Shannon's entropy and information theory 6 5 Entropy of ideal gas 10 .

How can this statement be justified? Entropy and Disorder Entropy is a measure of disorder. Ways to Lower Entropy For best results, consistent practice is necessary. level systems Examples of two level systems: -A Spin 1/2 particle -A 'two-level atom' An atom driven with an oscillating E-field whose frequency closely matches one of the atomic transition frequencies -Particle in a double-well potential E.g. This path will bring us to the concept of entropy and the second law of thermodynamics. 4.2.2. Thus the change in the internal energy of the system is related to the change in entropy, the absolute temperature, and the PV work done. This molecular-scale interpretation of entropy provides a link to the probability that a process will occur as illustrated in the next paragraphs. It is the measure of impurity in a bunch of examples. From a chemical perspective, we usually mean molecular disorder. Entropy (i.e. We investigate the dynamical behavior of the atom-photon entanglement in a V-type three-level quantum system using the atomic reduced entropy. The increase of entropy principle can be summarized as follows: Sgen > 0 Irreversible process Sgen = 0 Reversible process Sgen < 0 Impossible process Fig. The term and the concept are used in diverse fields, from classical thermodynamics, where it was first recognized, to the microscopic description of nature in statistical physics, and to the principles of information theory. The amount of entropy depends on the number of possible energy levels that the individual particles can have. Question 9) K+K Chapter 6, Problem 6 Entropy of Mixing. It can be seen from Figure 7 that the weight of each indicator is different, indicating that the importance of each indicator is different, and the focus of government management is also different. It is shown that an atom and photons are entangled at the steady-state; however disentanglement can also be achieved in an special condition. Entropy is given as. It's based on the Second Law of Thermodynamics, which states that the total entropy of an isolated system cannot decrease with time. On a cold winter day, Pelle spills out 1.0 dl of water with a temperature of 20 C. . The entropy of any substance is a function of the condition of the substance. Also, scientists have concluded that in a spontaneous process the entropy of process must increase. The result is an underdetermined system of linear equations, with three known values (the mutual information terms) and four unknown values (the partial information terms). Entropy. To address the description of entropy on a microscopic level, we need to state some results concerning microscopic systems. Entropy is mainly associated with heat and temperature. Our motivation is to discuss the entropy squeezing from another point of view by considering the entropy squeezing for the field instead of the atom. b) this is possible because the entropy of an isolated system can decrease. All you need to know is the energy level formula (E n= n ). The probability of finding the particle in first level is 0.38, for second level 0.36, and for third level it is 0.26. Entropy is the tendency of complex systems, to progressively move towards chaos, disorder, death, and deterioration. Thus, measuring the entropy level of the universe sheds light on both the . It can be expresses by 'S'=q/t The term is coined by Rudolf Clausius. However, in a gas the particles are free to move randomly and with a range of speeds.

randomness) of the system increases when the pressure decreases from 3 atm to 1 atm. We will illustrate the concepts by minima) of a function, e.g. The past three lectures: we have learned about thermal energy, how it is stored at the microscopic level, and how it can be transferred from one system to another. It will even increase more when water is evaporated to steam (gas). 4: The entropy of a substance increases ( S > 0) as it transforms from a relatively ordered solid, to a less-ordered liquid, and then to a still less-ordered gas. The level of chaos in the data can be calculated using entropy of the system. 3. We calculate the atomic spin-squeezing, the atomic entropy-squeezing, and their variances. Example: N = 20,000; E = 10,000; three energy levels 1=0, 2=1, 3=2. We study the dynamics of global quantum discord and von Neumann entropy for systems composed of two, three, and four two-level atoms interacting with the single-mode coherent field under the influence of a nonlinear Kerr medium. Higher entropy indicates higher uncertainty and a more chaotic system. For processes involving an increase in the number of microstates, W f > W i, the entropy of the system increases, S > 0. Because work is obtained from ordered molecular motion, the amount of entropy is also a measure of the molecular disorder, or randomness, of a system.